Vect&3d 1
Vect&3d 1
SECTION-A [FUNDAMENTAL]
VECTORS
Q.1 Find the value of so that the vectors a 2î ĵ k̂ and b î 2 ĵ 3k̂ are perpendicular to each
other.
Q.2 If a + b + c = 0 and | a | 3 , | b | 5 and | c | 7 , show that the angle between a and b is 60º.
Q.3 Find the angle between the vector a î ˆj k̂ and b î ˆj k̂ .
Q.4 Write the value of p for which a 3î 2 ĵ 9k̂ and b î pˆj 3k̂ are parallel vector..
Q.5 Find the value of p, if ( 2î 6 ĵ 27 k̂ ) × ( î 3ˆj pk̂ ) = 0 .
Q.6 If a , b, c are three vectors such that a . b a . c and a b a c , a 0 , then show that b c .
Q.7 Write a vector of magnitude 15 units in the direction of vector i 2ˆj 2k̂ .
Q.8 What is the cosine of theangle which the vector 2 î ĵ k̂ makes with y-axis?
Q.9 Let a î ĵ , b 3ˆj k̂ and c 7î k̂ . Find a vector d which isperpendicular to both a and b and
c.d =1.
Q.11 What are the direction cosines of a line, which makesequal angles with the co-ordinate axes ?
Q.12 Find a unit vector perpendicular to each of the vectors a b and a b , where a 3î 2ˆj 2k̂ and
b î 2 ĵ 2k̂ .
Q.13 Write the value of î ˆj · k̂ î · ĵ .
Q.14 Let a î 4ˆj 2k̂ , b 3î 2ˆj 7k̂ and c 2î ˆj 4k̂ . Find a vector p which is perpendicular to
both a and b and p · c = 18.
Q.15 Find | x | , if for a unit vector a , ( x a ) · ( x a ) = 15.
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Q.16 L and M are two points with position vectors 2a b and a 2b respectively. Write the position vector
of a point N which divides the line segment LM in the ratio 2 : 1 externally.
Q.17 Find the value of ‘p’ for which the vectors 3iˆ 2ˆj 9kˆ and ˆi 2pjˆ 3kˆ are parallel.
ˆ b ˆi 2jˆ kˆ and c 3iˆ ˆj 2kˆ
Q.18 Find a.(b c) , if a 2iˆ ˆj 3k,
Q.19 Show that the four points A, B, C and D with position vectors 4iˆ 5jˆ k,
ˆ ˆj k,3
ˆ ˆi 9 ˆj 4 kˆ and
4( ˆi ˆj k)
ˆ respectively are coplanar..
Q.20 The scalar product of the vector a ˆi ˆj kˆ with a unit vector along the sum of vectors
b 2iˆ 4ˆj 5kˆ and c ˆi 2ˆj 3kˆ is equal to one. Find the value of and hence find the unit vector
along b c
Q.21 Find a vector of magnitude 171 which is perpendicular to both of the vectors a ˆi 2ˆj 3kˆ
and b 3iˆ ˆj 2kˆ .
Q.24 Show that the points A, B, C with position vectors 2î ˆj k̂ , î 3 ĵ 5k̂ and 3î 4ˆj 4k̂ respectively,,
are the vertices of a right-angled triangle. Hence find the area of the triangle.
Q.25 If a 2î ˆj 2k̂ and b 7 î 2 ĵ 3k̂ , then express b in the form of b b1 b 2 ,
where b1 is parallel to a and b2 is perpendicular to a.
Q.26 Find | a b | , if a î 7 ĵ 7 k̂ and b 3î 2ˆj 2k̂ .
Q.27 Writetheposition vector of apoint dividing theline segment joining pointsA and B with positionvectors
a and b externally in the ratio 1 : 4 where a 2î 3ˆj 4k̂ and b î ˆj k̂ .
Q.29 Let a , b and c be three vectors such that | a | 3 , | b | 4 , | c | 5 and each one of them being
perpendicular to thesum of the other two, find | a b c | .
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Q.30 Threevectors a , b and c satisfy thecondition a b c 0 . Evaluatethequantity = a . b b . c c . a ,
if | a | 1 , | b | 4 and | c | 2 .
Q.31 Find the area of the parallelogram whose adjacent sides are determined by the vectors a î ˆj 3k̂
and b 2î 7ˆj k̂ .
Q.32 In a regular hexagon ABCDEF, if AB a and BC b then express CD , DE , EF , FA , AC , AD ,
AE and CE in terms of a and b .
Q.33 Show that the pointsA ( 2î 3 ĵ 5k̂ ) , B ( î 2ˆj 3k̂ ) and C (7î k̂ ) are collinear..
1
Q.34 If a and b are unit vectors and is the angle between them, then prove that cos = | a b |.
2 2
Q.35 Find the volume of the parallelopiped whose adjacent sides are represented by a , b and c where
a 3î 2ˆj 5k̂ , b 2î 2 ĵ k̂ , c 4î 3 ĵ 2k̂ .
Q.36 If the position vectors of three consecutive vertices of any parallelogram are respectively
î ˆj k̂ , î 3 ĵ 5k̂ , 7î 9 ĵ 11 k̂ then, find the position vector of its fourth vertex.
xy 2
Q.37 ˆ ˆ
If a x î 2 j 5k̂ and b î yj zk̂ are linearly dependent, then find the value of .
z
Q.38 If a & b are non collinear vectors such that , p ( x 4 y )a ( 2 x y 1) b &
q ( y 2 x 2) a ( 2 x 3y 1) b , find x & y such that 3p 2q .
Q.39 a , b, c are three non zero vectors no two of them are parallel. If a b is collinear to c and b c is
collinear to a, then a b c is equal to
Q.41 A triangle has vertices (1, 1, 1) ; (2, 2, 2), (1, 1, y) and has the area equal to csc 4 sq. units. Find the
value of y.
Q.42 Vector V is perpendicular to the plane of vectors a 2î 3ˆj k̂ and b î 2 ĵ 3k̂ and satisfies the
condition V · ( î 2 ĵ 7 k̂ ) = 10. Find | V |2 .
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Q.51 Show that the four points A (4, 5, 1), B (0, –1, –1), C (3, 9, 4) and D (–4, 4, 4) are coplanar.
Q.52 If thex-coordinate of a point P on the join of Q(2, 2, 1) and R(5, 1, –2) is 4, then find its z-coordinate.
Q.53 Find the equation of the plane passing through the intersection of the planes, 3x – y + 2z – 4 = 0 and
x + y + z – 2 = 0 and the point (2, 2, 1).
Q.54 If the point (1, 1, P) and (–3, 0, 1) be equidistant from the plane
r .(3î 4 ĵ 12k̂ ) + 13 = 0, then find the value of P.
Q.55 Find thevector equation of theplane passing through the intersection of theplanes r .( î ĵ k̂ ) 6 and
r .( 2î 3 ĵ 4k̂ ) 5 , and the point (1, 1, 1).
Q.56 Show that theline r ( 2î 2 ĵ 3k̂ ) ( î ˆj 4k̂ ) is parallel to the plane r ·( î 5 ĵ k̂ ) 5 . Also, find
the distancebetween them.
Q.57 The equation of the plane which has the property that the point Q (5, 4, 5) is the reflection of
point P (1, 2, 3) through that plane, is ax + by + cz = d where a, b, c, d N.
Find the least value of (a + b + c + d).
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Q.2 If D,E,F are mid points of sides BC, CA, and AB respectively of a triangle ABC, and
î ˆj , ĵ k̂ , k̂ î are p.v. of points A,B and C respectively, then p.v. of centroid of DEF is-
î ĵ k̂ 2(î ˆj k̂ )
(A) (B) î ˆj k̂ (C) 2 ( î ˆj k̂ ) (D)
3 3
[3011711929]
Q.3 If D,E and F are midpoints of sides BC, CA and AB of a triangle ABC, then AD + BE + CF is equal
to-
(A) 0 (B) 2 BC (C) 2 AB (D) 2 CA [3011711980]
Q.4 If a line makes angle with the co-ordinate axis then cos2 + cos2 + cos 2equals to–
(A) –2 (B) –1 (C) 1 (D) 2 [3011712031]
Q.6 Let p is the p.v. of the orthocentre & g is the p.v. of the centroid of the triangle ABC where
circumcentre is the origin. If p = K g , then K =
(A) 3 (B) 2 (C) 1/3 (D) 2/3 [3011711765]
Q.7 A vector a has components 2p & 1 with respect to a rectangular cartesian system. The system is
rotated through a certain angle about the origin in the counterclockwise sense. If with respect to
the new system, a has components p + 1 & 1 then ,
(A) p = 0 (B) p = 1 or p = 1/3
(C) p = 1 or p = 1/3 (D) p = 1 or p = 1 [3011711816]
Q.8 The position vector of the points A and B are a and b respectively. If P divides AB is the ratio 3:
1 and Q is the mid point of AP, then the position vector of Q is- [3011711867]
ab a b 5a 3b 5a 3b
(A) (B) (C) (D)
2 2 8 8
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Q.9 If A = (x + 1) a + (2y – 3) b and B = 5 a – 2 b are two vectors such that 2 A = 3 B , & a , b are
non collinear vectors then- [3011711918]
(A) x = 13/2, y = 0 (B) x = 0, y = 3 (C) x = –13/2, y = 0 (D) None of these
Q.10 If the points P,Q,R,S are respectively î k̂ , î 2ˆj , 2î 3k̂ and 3î 2ˆj k̂ , then projection of
PQ on RS is- [3011711969]
(A) 4/3 (B) – 4/3 (C) 3/4 (D) –3/4
Q.11 Two vectors p , q on a plane satisfy p q 13 , p q 1 and p 3 .
The angle between p and q , is equal to [3011712020]
(A) (B) (C) (D)
6 4 3 2
Q.12 The set of values of c for which the angle between the vectors cx i 6 j 3k & x i 2 j 2 cx k is
acute for every x R is [3011712071]
(A) (0, 4/3) (B) [0, 4/3] (C) (11/9, 4/3) (D) [0, 4/3)
Q.13 Let u, v, w be such that u 1, v 2, w 3 . If the projection of v along u is equal to that
of w along u and vectors v , w are perpendicular to each other then u v w equals
Q.14 If p & s are not perpendicular to each other and r x p qx p & r . s = 0, then r = [3011712205]
q . p q . s
(A) p . s (B) q p (C) q p (D) q p for all scalars
p . s p . s
Q.15 Let a a1 i a2 j a3 k ; b b1 i b2 j b3 k ; c c1 i c2 j c3 k be three non-zero vectors such
that c is a unit vector perpendicular to both a & b . If the angle between a & b is then
6
2
a1 b1 c1
a2 b2 c2 =
a3 b3 c3
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Q.16 If the volume of the tetrahedron with edges î ˆj k̂ , î aĵ k̂ and î 2ˆj k̂ is 6 cubic units, then
a is-
(A) 1 (B) – 1 (C) 2 (D) – 17 [3011712307]
Q.17 If a , b, c be any three unit vectors such that 3a 4b 5c = 0, then- [3011712256]
(A) a || b (B) b || c (C) a b (D) None of these
Q.18 If a , b, c be any three unit vectors such that a and b are perpendicular to each other and
2a 3b c , then value of is- [3011712358]
(A) 1 (B) 5 (C) 13 (D) 13
Q.19 If a , b, c are three non-zero vectors such that a + b + c= 0 and m = a b + b c+ c a , then
(A) m < 0 (B) m > 0 (C) m = 0 (D) m = 3 [3011712112]
Q.20 Let AB 3î ˆj , AC 2î 3 ĵ and DE 4î 2 ĵ . A
Q.22 Position vectors of the four angular points of a tetrahedron ABCD are A(3, – 2, 1); B(3, 1, 5);
C(4, 0, 3) and D(1, 0, 0). Acute angle between the plane faces ADC and ABC is [3011712265]
(A) tan–1 5 2 (B) cos–1 2 5 (C) cosec–1 5 2 (D) cot–1 3 2
Q.23 a , b and c be three vectors having magnitudes 1, 1 and 2 respectively. If
a × ( a × c ) + b = 0, then the acute angle between a & c is [3011712367]
(A) /6 (B) /4 (C) /3 (D) 5 12
Q.24 A vector of magnitude 5 5 coplanar with vectors î 2 ĵ & ĵ 2k̂ and the perpendicular vector 2î ĵ 2k̂
is
(A) ± 5 5î 6ˆj 8k̂ (B) ±
5 5î 6ˆj8k̂ [3011712316]
(C) ± 5 5 5î 6ˆj 8k̂
(D) ± 5î 6ˆj8k̂
Q.25 ( a + 2 b– c) {( a – b) × ( a – b– c)} is equal to [3011712418]
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3-DIMENSIONAL G E O M E T RY
Q.1 The equation of the plane which is parallel to the plane x – 2y + 2z = 5 and whose distance from
the point (1, 2, 3) is 1, is [3011712322]
(A) x – 2y + 2z = 3 (B) x – 2y + 2z + 3 = 0
(C) x – 2y + 2z = 6 (D) x – 2y + 2z + 6 = 0
Q.2 The intercept made by the plane r . n q on the x-axis is [3011712373]
q
î . n q
(A)
î . n
(B)
q
(C) î . n q (D) | n |
Q.3 If the plane 2x – 3y + 6z – 11 = 0 makes an angle sin–1(k) with x-axis, then k is equal to
(A) 3 2 (B) 2/7 (C) 2 3 (D) 1 [3011712424]
Q.4 A variable plane forms a tetrahedron of constant volume 64 K3 with the coordinate planes and the
origin, then locus of the centroid of the tetrahedron is [3011712128]
3 3 3
(A) x + y + z = 6K 3 (B) xyz = 6k3
Q.5 Which of the following planes are parallel but not identical? [3011712179]
P1 : 4x – 2y + 6z = 3
P2 : 4x – 2y – 2z = 6
P3 : –6x + 3y – 9z = 5
P4 : 2x – y – z = 3
x 2 y 9 z 13 x a y7 z2
Q.6 The value of 'a' for which the lines = and intersect, is
1 2 3 1 2 3
(A) – 5 (B) – 2 (C) 5 (D) – 3
[3011711239]
x 1 y 2 z 3
Q.7 For the line , which one of the following is incorrect? [3011712230]
1 2 3
(A) it lies in the plane x – 2y + z = 0
x y z
(B) it is same as line
1 2 3
(C) it passes through (2, 3, 5)
(D) it is parallel to the plane x – 2y + z – 6 = 0
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Q.9 The plane ax + by + cz = 1 meets the co-ordinate axes in A, B and C. The centroid of the triangle
is
a b c 3 3 3 1 1 1
(A) (3a, 3b, 3c) (B) , , (C) , , (D) , ,
3 3 3 a b c 3a 3b 3c
[3011712281]
Q.10 The equation of the plane passing through the point (–1, 3, 2) and perpendicular to each of the
planes x + 2y + 3z = 5 and 3x + 3y + z = 0, is -
(A) 7x – 8y + 3z – 25 = 0 (B) 7x – 8y + 3z + 25 = 0
(C) –7x + 8y – 3z + 5 = 0 (D) 7x – 8y – 3z + 5 = 0 [3011712340]
Q.11 The equation of the plane through intersection of planes x + 2y + 3z = 4 and 2x + y – z = – 5 and
perpendicular to the plane 5x + 3y + 6z + 8 = 0 is
(A) 7x – 2y + 3z + 81 = 0 (B) 23x + 14y – 9z + 48 = 0
(C) 51x + 15y – 50z + 173 = 0 (D) None of these [3011712289]
Q.12 The equation of the plane passing through the line of intersection of the planes
x + y + z = 1 and 2x + 3y – z + 4 = 0 and parallel to x-axis is - [3011712238]
(A) y – 3z – 6 = 0 (B) y – 3z + 6 = 0 (C) y – z – 1 = 0 (D) y – z + 1 = 0
1 1 1
Q.15 If the direction cosines of a line are , , , then - [3011712283]
c c c
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Q.16 The equations of the line passing through the point (1, 2, –4) and perpendicular to the two lines
x 8 y 19 z 10 x 15 y 29 z 5
and will be [3011712434]
3 16 7 3 8 5
x 1 y 2 z 4 x 1 y 2 z 4
(A) (B)
2 3 6 2 3 8
x 1 y 2 z 4
(C) (D) None of these
3 2 8
Q.17 Equation of the plane through (3, 4, –1) which is parallel to the plane r . ( 2î 3ˆj 5k̂ ) + 7 = 0 is
[3011712391]
(A) r . ( 2î 3ˆj 5k̂ ) + 11 = 0 (B) r . (3î 4 ĵ k̂ ) + 11 = 0
(C) r . (3î 4 ĵ k̂ ) + 7 = 0 (D) r . ( 2î 3ˆj 5k̂ ) –7 = 0
Q.18 Equation of the plane containing the lines. r = î 2ˆj k̂ ( î 2ˆj k̂ ) and r = î 2ˆj k̂ ( î ˆj 3k̂ )
is
[3011712442]
(A) r . (7 î 4 ĵ k̂ ) = 0 (B) 7(x – 1) – 4(y – 1) – (z + 3) = 0
(C) r . ( î 2 ĵ k̂ ) = 0 (D) r . ( î ˆj 3k̂ ) = 0
x 3 y 5 z 1
Q.19 If the line = = is parallel to the plane 6x + 8y + 2z – 4 = 0, then k
2 k 2k
(A) 1 (B) –1 [3011712142]
(C) 2 (D) 3
Q.20 If x & y are two non collinear vectors and a, b, c represent the sides of a ABC satisfying
(a b) x + (b c) y + (c a) x y = 0 then ABC is [3011712244]
(A) an acute angle triangle (B) an obtuse angle triangle
(C) a right angle triangle (D) a scalene triangle
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[JEE ADVANCED]
VECTOR
[ SINGLE CORRECT CHOICE T Y PE]
Q.1 Consider ABC with A (a ) ; B ( b) & C ( c) . If b . (a c) = b . b a . c ; b a = 3;
c b =4thentheanglebetweenthemedians A M & BD is [3011712214]
1 1
(A) cos1 (B) cos1
5 13 13 5
1 1
(C) cos1
(D) cos1
5 13 13 5
Q.2
Let r a b sin x b c cos y 2 c a , where a , b, c are non-zero and non-coplanar vectors.
20
If r is orthogonal to a b c , then the minimum value of 2 (x2 + y2), is [3011711032]
(A) 20 (B) 25 (C) 30 (D) 35
Q.3
Let O be an interior point of ABC such that 2 O A 5 O B 10 O C 0 . If the ratio of the area of
ABC to the area of AOC is t, where 'O' is the origin. The value of [t], is
(Where [ ] denotes greatest integer function.) [3011711419]
(A) 1 (B) 2 (C) 3 (D) 4
Q.4 If a and b are two vectors such that | a | 1 , | b | 4 , a · b 2 . If c ( 2a b) 3b then the angle
between b and c , is [3011710930]
2 5
(A) (B) (C) (D)
6 3 3 6
Q.5 The minimum area of the triangle whose vertices are A(–1, 1, 2); B(1, 2, 3) and C(t, 1, 1)
where t is a real number, is [3011710879]
1 1 1 3
(A) (B) (C) (D)
2 2 3 2
Q.6 Points X & Y are taken on the sides QR & RS , respectively of a parallelogram PQRS, so that
QX 4 XR & RY 4 YS . The line XY cuts the line PR at Z . If PZ k PR then k is equal to.
[3011710861]
20 21 22 23
(A) (B) (C) (D)
27 25 23 20
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Q.7 The three vectors î ˆj , ĵ k̂ , k̂ î taken two at a time form three planes. The three unit vectors drawn
perpendicular to these three planes form a parallelopiped of volume : [3011712193]
(A) 1/3 (B) 4 (C) 3 3 4 (D) 4 3 3
Q.8 In a ABC, the side length BC, CA and AB are consecutive positive integers in increasing order. Let
a , b and c be the position vectors of vertices A, B and C respectively. If ( c a ) · ( b c ) = 0, then
the value of a b b c c a is equal to
(A) 3 (B) 6 (C) 12 (D) 24
[PARAGRAPH TYPE]
Paragraph for questions nos. 9 to 11
Consider three vectors p î ˆj k̂ , q 2î 4 ĵ k̂ and r î ˆj 3k̂ and let s be a unit vector, then
[3011712295]
Q.9 p, q and r are
(A) linearly dependent
(B) can form the sides of a possible triangle
(C) such that the vectors (q r ) is orthogonal to p
(D) such that each one of these can be expressed as a linear combination of the other two
Q.10 if ( p q ) × r = up vq w r , then (u + v + w) equals to
(A) 8 (B) 2 (C) – 2 (D) 4
Q.11 The magnitude of the vector ( p · s )(q r ) + (q · s )( r p) + ( r · s )( p q) is
(A) 4 (B) 8 (C) 18 (D) 2
2
Q.12 a b 2c · (a b) has the value equal to
(A) 12 (B) 10 (C) 8 (D) 6
2
Q.13 a bc equals
(A) 5 (B) 6 (C) 7 (D) 8
Q.14 Difference between of the maximum and minimum value of a b is equal to
(A) 2 (B) 3 (C) 4 (D) 1
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[ REASONING T Y PE]
Q.15 Consider three vectors a , b and c
Statement-1: a b ( î a ) · b î (ˆj a ) · b ĵ ( k̂ a ) · b k̂
Statement-2: c ( î · c ) î (ˆj· c) ĵ ( k̂ · c) k̂
(A) Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1.
(B) Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for statement-1.
(C) Statement-1 is true, statement-2 is false.
(D) Statement-1 is false, statement-2 is true. [3011712171]
Q.16 Statement-1: Let the vector a î ĵ k̂ be vertical. The line of greatest slope on a plane with
normal b 2î ˆj k̂ is along the vector î 4ˆj 2k̂ .
Statement-2: If a is vertical, then the line of greatest slope on a plane with normal b is along the
vector (a b) b .
(A) Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1.
(B) Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for statement-1.
(C) Statement-1 is true, statement-2 is false.
(D) Statement-1 is false, statement-2 is true. [3011712222]
Q.18 Let a and b be two non-zero and non-collinear vectors then which of the following is/are always
correct?
(A) a b = a b î î + a b ˆj ĵ + a b k̂ k̂
(B) a · b = (a · î ) ( b · î ) + (a · ĵ) ( b · ĵ) + (a · k̂ ) ( b · k̂ )
(C) if u = â (â · b̂) b̂ and v â b̂ then | u || v |
(D) if c a (a b) and d b (a b) then c d 0 . [3011712375]
Q.19 L et O be an interior point of ABC such that OA 2OB 3OC 0 and areas of ABC, AOB,
1
BOC and AOC are denoted by 1, 2, 3 and 4 respectively then is
min . ( 2 , 3 , 4 )
divisible by
(A) 2 (B) 3 (C) 4 (D) 6
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3
(C) Area (ABC). (R)
3
3
(D) Distance between orthocentre and centroid. (S)
6
(E) Distance between orthocentre and circumcentre. (T) (0, 0, 0)
1 1 1
(F) Distance between circumcentre and centroid. (U) , ,
2 2 2
1 1 1
(G) Incentre of ABC. (V) , ,
3 3 3
1 2 1
(H) Centroid of ABC (W) , ,
1 2 3 1 2 3 1 2 3
[3011712426]
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Q.24 Let P and Q are two points in xy-plane on the curve y = x7 – 2x5 + 5x3 + 8x + 5 such that
Q.25 Given three points on the xy plane on O(0, 0), A(1, 0) and B(–1, 0). Point P is moving on the plane
satisfying the condition P A · P B + 3 O A · O B = 0 [3011710726]
If the maximum and minimum values of P A P B are M and m respectively then find the value of M2 + m2.
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Q.26 Given a tetrahedron D-ABC with AB = 12 , CD = 6. If the shortest distance between the skew lines
AB and CD is 8 and the angle between them is , then find the volume of tetrahedron.
6
[3011710777]
Q.27 Let ( p q) r (q · r ) q ( x 2 y 2 )q (14 4x 6 y)p and ( r · r ) p r where p and q are
two non-zero non-collinear vectors and x and y are scalars. Find the value of (x + y).
[3011710828]
Q.28 Let OA = a ; OB = 100 a 2 b and OC = b where O, A, and C are non collinear points. Let P
denotes the area of the parallelogram with OA and OC as adjacent sides and Q denotes the area of the
quadrilateral OABC. If Q = P. Find the value of . [3011710736]
Q.29 In ABC, a point P is chosen on side A B so that AP : PB = 1 : 4 and a point Q is chosen on the side
MC
B C so that CQ : QB = 1 : 3. Segment C P and A Q intersect at M. If the ratio PC is expressed as a
a
rational number in the lowest term as , find (a + b). [3011711041]
b
Q.30 Given f 2(x) + g2(x) + h2(x) 9 and U(x) = 3 f (x) + 4 g (x) + 10 h(x),where f (x), g (x) and h (x) are
continuous x R. If maximum value of U(x) is N , then find N. [3011711470]
2
Q.31 Let two non-collinear vectors a and b inclined at an angle be such that | a | 3 and | b | 4 .
3
A point P moves so that at any time t the position vector OP (where O is the origin) is given as
OP = (et + e–t) a + (et – e–t) b . If the least distance of P from origin is 2 a b
where a, b N then find the value of (a + b). [3011711572]
Q.32 If x , y are two non-zero and non-collinear vectors satisfying [3011711725]
[(a – 2)2 + (b – 3) + c] x + [(a – 2)2 + (b – 3) + c] y + [(a – 2)2 + (b – 3) + c] (x y) = 0
where , , are three distinct real numbers, then find the value of (a2 + b2 + c2).
Q.34 The position vectors of the points A, B, C are respectively (1, 1, 1) ; (1, 1, 2); (0, 2, 1). Find a unit
vector parallel to the plane determined by ABC & perpendicular to the vector (1, 0, 1) .
[3011711040]
Q.35 Given that a,b,p,q are four vectors such that a b p , b .q 0 & ( b ) 2 1 , where µ is a scalar then
prove that ( a .q ) p ( p .q ) a p .q . [3011710981]
88
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
3 - D I M E N S I O N A L G E O M E T RY
[ SINGLE CORRECT CHOICE T Y PE]
Q.1 Equation of the line in the plane x + 3y – z = 9, which is perpendicular to the line
r î ˆj k̂ 2î ˆj k̂ and passing through a point where the plane P meets the given line, is
x 3 y2 z x 3 y2 z
(A) (B)
2 1 5 2 1 5
x 3 y2 z x 3 y2 z
(C) (D)
5 1 2 1 5 2
1 t
Q.2 The distance between the line x= 2 + t, y = 1 + t, z = – and the plane r · ( î 2ˆj 6k̂ ) 10 , is
2 2
1 1 1 9
(A) (B) (C) (D)
6 41 7 41
b
Q.3 If the lines x = 1 + a, y = –3 – a, z = 1 + a and x = , y = 1 + b, z = 2 – b are coplanar,,
2
then is equal to
(A) –3 (B) 2 (C) 1 (D) –2
Q.4 If the equation of the plane passing through (1, 2, 0) and which contains the line
x 3 y 1 z2
= = is 6x + y + z = k, then the value of (2 – 5 – k) equals
3 4 2
(A) 3 (B) 4 (C) 5 (D) 6
x 1 y 1 z 10
Q.5 Consider line L = = . Point P(1, 0, 0) and Q are such that PQ is perpendicular to
2 3 8
line L and the mid-point of PQ lies on the line L then Q is
(A) (3, –4, –2) (B) (5, –8, –4) (C) (1, –1, –10) (D) (2, –3, 8)
Q.6 The value of m for which straight line 3x – 2y + z + 3 = 0 = 4x – 3y + 4z + 1 is parallel to the plane
2x – y + mz – 2 = 0 is
(A) – 2 (B) 8 (C) 11 (D) – 18
Q.7 Let OA, OB, OC be coterminous edges of a cube. If l, m, n be the shortest distance between the sides
OA, OB, OC and their respective skew body diagonals to them respectively then
1 1 1 1 1 1
2 2 2 : 2
is equal to
l m n OA OB OC 2
2
1 1
(A) 2 (B) 3 (C) (D)
2 3
Q.8 The distance of the z-axis from the image of the point M (2, –3, 3) in the plane x – 2y – z + 1 = 0, is
(A) 1 (B) 2 (C) 2 (D) 4
89
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
[ PARAGRAPH T Y PE]
Paragraph for question nos. 9 and 10
Consider a plane
x + y – z = 1 and the point A(1, 2, –3)
A line L has the equation
x = 1 + 3r
y=2–r
z = 3 + 4r [3011712346]
Q.9 The co-ordinate of a point B of line L, such that AB is parallel to the plane, is
(A) 10, –1, 15 (B) –5, 4, –5 (C) 4, 1, 7 (D) –8, 5, –9
Q.10 Equation of the plane containing the line L and the point A has the equation
(A) x – 3y + 5 = 0 (B) x + 3y – 7 = 0 (C) 3x – y – 1 = 0 (D) 3x + y – 5 = 0
Q.11 If the coordinates of point C on plane P such that AC + BC is minimum are (, , ), then value of ( +
+ ) equals
(A) 1 (B) 2 (C) 3 (D) 4
Q.13 Coordinates of point D on plane P such that | AD – BD | is minimum are (k1, k2, k3), then the value of
(k1 + k2 + k3) equals
(A) 1 (B) 2 (C) 3 (D) 4
90
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
[ REASONING T Y PE]
x 4 y 5 z 1 x 2 y 1 z
Q.17 Given lines and
2 4 3 1 3 2
Statement-1: The lines intersect.
Statement-2: They are not parallel.
(A) Statement-1 is true, statement-2 is true and statement-2 is correct explanation for statement-1.
(B) Statement-1 is true, statement-2 is true and statement-2 is NOT the correct explanation for statement-1.
(C) Statement-1 is true, statement-2 is false.
(D) Statement-1 is false, statement-2 is true. [3011712120]
Q.19 If a line passing through (–2, 1, p) and (4, 1, 2) is perpendicular to the vector 2î 7ˆj 6k̂ and
parallel to the plane containing the vectors î qk̂ and qˆj pk̂ then the ordered pair (p, q) is
1 1
(A) 1, (B) (0, 0) (C) (–1, 0) (D) 0,
2 3
Q.20 In 3-D space, let three lines L1, L2 and L3 be such that
L1 : intersecting the z-axis at P(0, 0, 2) and does not meet the x-y plane
L2 : passing through the origin and through the point P.
L3 : passing through the origin and making positive angles (, , ) with co-ordinate axes and 45° angle
with line L1
Identify the which of the following statement(s) is(are) correct?
(A) area of the triangle formed by the lines L1 , L2 and L3 is 2 square units.
(B) area of the triangle formed by the lines L1, L2 and L3 is 8 square units.
(C) If = 60°, then equation of L1 is x = y; z = 2.
(D) If = 60°, then equation of L1 is x + y = 0 and z = 2.
91
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
92
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93
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.10 A line AB in three-dimensional space makes angles 45° and 120° with the positive x -axis and the
positive y-axis respectively. If AB makes an acute angle with the positive z-axis, then equals
(A) 30° (B) 45° (C) 60° (D) 75° [3011712739]
[AIEEE-2010]
Q.11 Statement-1 : The point A(3, 1, 6) is the mirror image of the point B(1, 3, 4) in the plane x – y + z = 5.
Statement-2 : The plane x – y + z= 5 bisects the line segment joining A(3, 1, 6) and B(1, 3, 4).
(A) Statement-1 is true, Statement-2 is true and Statement-2 is the correct explanation of Statement-1.
(B) Statement-1 is true, Statement-2 is false and Statement-2 is not the correct explanation of Statement-1
(C) Statement-1 is true, Statement-2 is false
(D) Statement-1 is false, Statement-2 is true. [3011712790]
[AIEEE-2010]
1
7
Q.12 If a 1 3î k̂ and b 2î 3ˆj 6k̂ , then the value of 2a b · a b a 2b is
10
(A) –5 (B) –3 (C) 5 (D) 3 [3011712485]
[AIEEE-2011]
Q.13 The vectors a and b are not perpendicular and c and d are two vector satisfying
b c b d and a · d 0 . Then the vector d is equal to [3011712536]
b · c a · c b · c a · c
(A) b c (B) c b (C) b c (D) c b
a · b a · b
a · b a · b
[AIEEE-2011]
y 1 z 3 5
Q.14 If the angle between the line x = and the plane x + 2y + 3z = 4 is cos–1 , then
2 14
equals [3011712638]
(A) 2/3 (B) 3/2 (C) 2/5 (D) 5/2 [AIEEE-2011]
Q.15 Statement-1 : The point A(1, 0, 7) is the mirror image of the point B (1, 6, 3) in the line
x y 1 z 2
. [3011712689]
1 2 3
x y 1 z 2
Statement 2 : The line : bisects the line segment joining A(1, 0, 7) and B(1, 6, 3).
1 2 3
(A) Statement-1 is true, Statement-2 is true and Statement-2 is the correct explanation of Statement-1.
(B) Statement-1 is true, Statement-2 is false and Statement-2 is not the correct explanation of Statement-1
(C) Statement-1 is true, Statement-2 is false
(D) Statement-1 is false, Statement-2 is true. [AIEEE-2011]
Q.16 Let â and b̂ be two unit vectors. If the vectors c â 2b̂ and d 5â 4b̂ are perpendicular to each
other, then the angle between â and b̂ [3011712740]
(A) (B) (C) (D) [AIEEE-2012]
3 4 6 2
Q.17 Let ABCD be a parallelogram such that AB q , AD p and BAD be an acute angle. If r is the
vector that coincides with the altitude directed from the vertex B to the side AD, then r is given by
p·q 3 p · q
(A) r q p (B) r 3q p [3011712791]
p·p p ·p
3 p · q p·q
(C) r 3q p (D) r q p [AIEEE-2012]
p ·p p·p
94
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.18 An equation of a plane parallel to the plane x – 2y + 2z – 5 = 0 and at a unit distance from the origin is
(A) x – 2y + 2z – 1 = 0 (B) x – 2y + 2z + 5 = 0 [3011712490]
(C) x – 2y + 2z – 3 = 0 (D) x – 2y + 2z + 1 = 0 [AIEEE-2012]
x 1 y 1 z 1 x 3 yk z
Q.19 If the line and intersect, then k is equal to [3011712541]
2 3 4 1 2 1
9 2
(A) (B) 0 (C) – 1 (D) [AIEEE-2012]
2 9
x2 y 3 z 4 x 1 y 4 z 5
Q.20 If the lines = = and = = are coplanar, then k can have
1 1 k k 2 1
(A) exactly one value (B) exactly two values [3011712592]
(C) exactly three values (D) any value [JEE Main 2013]
Q.21 If the vectors AB 3î 4k̂ and AC 5î 2ˆj 4k̂ are the sides of a triangle ABC, then the length of
the median through A is [3011712643]
(A) 72 (B) 33 (C) 45 (D) 18 [JEE Main 2013]
Q.25 The angle between the lines whose direction cosines satisfy the equations l + m + n = 0 and
l2 = m2 + n2 is
(A) (B) (C) (D) [JEE Main 2014]
2 3 4 6
Q.26 Let a , b and c be three non-zero vectors such that no two of them are collinear and
1
(a b) c = b c a . If is the angle between vectors b and c , then a value of sin is
3
2 2 3 2 2 2
(A) (B) (C) (D)
3 3 3 3
[JEE Main 2015]
95
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.27 The equation of the plane containing the line 2x – 5y + z = 3; x + y + 4z = 5, and parallel to the plane,
x + 3y + 6z = 1, is
(A) x + 3y + 6z = 7 (B) 2x + 6y + 12z = –13
(C) 2x + 6y + 12z = 13 (D) x + 3y + 6z = –7 [JEE Main 2015]
x 2 y 1 z 2
Q.28 The distance of the point (1, 0, 2) from the point of intersection of the line = = and the
3 4 12
plane x – y + z = 16, is [JEE Main 2015]
(A) 3 21 (B) 13 (C) 2 14 (D) 8
Q.29 The distance of the point (1, – 5, 9) from the plane x – y + z = 5 measured along the line
x = y = z is [JEE Main 2016]
20 10
(A) (B) 3 10 (C) 10 3 (D)
3 3
x 3 y 2 z 4
Q.30 If the line, lies in the plane, lx + my – z = 9, then l2 + m2 is equal to
2 1 3
(A) 2 (B) 26 (C) 18 (D) 5 [JEE Main 2016]
3
Q.31 Let a , b and c be three unit vectors such that a ( b c) = (b c ) . If b is not parallel to c , then
2
the angle between a and b is [JEE Main 2016]
5 3 2
(A) (B) (C) (D)
6 4 2 3
Q.32 If the image of the point P (1, – 2, 3) in the plane, 2x + 3y – 4z + 22 = 0 measured parallel to the line,
x y z
= = is Q, then PQ is equal to [JEE (Main) 2017]
1 4 5
(A) 3 5 (B) 2 42 (C) 42 (D) 6 5
Q.33 The distance of the point (1, 3, – 7) from the plane passing through the point (1, – 1, – 1) having normal
x 1 y 2 z 4 x 2 y 1 z 7
perpendicular to both the lines = = and = = is
1 2 3 2 1 1
20 10 5 10
(A) (B) (C) (D)
74 83 83 74
[JEE (Main) 2017]
Q.34 Let a = 2î ˆj 2k̂ and b = î ˆj . Let c be a vector such that | c a | = 3, (a b) c = 3 and the
angle between c and a b be 30°. Then a · c is equal to
25 1
(A) (B) 2 (C) 5 (D) [JEE (Main) 2017]
8 8
96
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.1 Show by vector methods, that the angular bisectors of a triangle are concurrent and find an expression
for the position vector of the point of concurrency in terms of the position vectors of the vertices.
[JEE '2001 (Mains)]
Q.2 Find 3–dimensional vectors v 1, v 2 , v 3 satisfying
v 1 v 1 = 4, v 1 v 2 = –2, v 1 v 3 = 6, v 2 v 2 = 2, v 2 v 3 = –5, v 3 v 3 = 29.
[JEE '2001 (Mains)]
2 2 2
Q.3 If a, b and c are unit vectors, then a b b c c a does NOT exceed
(A) 4 (B) 9 (C) 8 (D) 6
[JEE '2001 (Screening)]
Q.4 Let a î k̂ , b x î ĵ (1 x )k̂ and c yî x ˆj (1 x y)k̂ . Then [ a, b, c] depends on
(A) only x (B) only y (C) NEITHER x NOR y (D) both x and y
[JEE '2001 (Screening)]
Q.5 Let A (t ) = f 1 (t )i f 2 (t )j and B( t ) g1 ( t ) i g2 ( t ) j , t [0, 1], where f1, f2, g1, g2 are
continuous functions. If A (t ) and B( t ) are nonzero vectors for all t and A(0) = 2i 3j ,
A(1) = 6i 2j , B(0) = 3i 2j and B(1) = 2i 6j , then show that A (t ) and B(t ) are parallel for
some t. [JEE '2001 (Mains)]
Q.6 If a and b are two unit vectors such that a + 2 b and 5 a – 4 b are perpendicular to each other then
the angle between a and b is [3011711479]
(A) 450 (B) 600 (C) cos–1 1 3 (D) cos–1 2 7
[JEE 2002(Screening)]
Q.7 Let V 2î ˆj k̂ and W î 3k̂ . If U is a unit vector, then the maximum value of the scalar triple
product U V W is [3011711530]
Q.8 Let V be the volume of the parallelopiped formed by the vectors a a1î a 2 ˆj a 3k̂ ,
b b1î b 2 ˆj b 3k̂ , c c1î c 2 ĵ c 3k̂ . If ar , br , cr , where r = 1, 2, 3, are non-negative real
3
numbers and a r b r c r = 3L, show that V L3. [3011711581]
r 1
[JEE 2002(Mains), 5]
9 7
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.9 If a = î aˆj k̂ , b = ˆj ak̂ , c = aî k̂ , then find the value of ‘a’ for which volume of
parallelopiped formed by three vectors as coterminous edges, is minimum, is [3011711632]
1 1 1
(A) (B) – (C) ± (D) none
3 3 3
[JEE 2003(Scr.)]
Q.10 Find the equation of the plane passing through the points (2, 1, 0) , (5, 0, 1) and (4, 1, 1).
[3011711683]
[ JEE 2003]
Q.11 If P is the point (2, 1, 6) then find the point Q such that PQ is perpendicular to the plane in (i) and the mid
point of PQ lies on it. [3011711683]
[ JEE 2003]
Q.12 If u , v , w are three non-coplanar unit vectors and , , are the angles between u and v ,
v and w , w and u respectively and x , y, z are unit vectors along the bisectors of the angles , ,
1 2
respectively. Prove that x y y z z x u v w sec 2 sec 2 sec 2 .
16 2 2 2
[3011711734]
[JEE 2003]
x 1 y 1 z 1 x 3 y k z
Q.13 If the lines and intersect, then k = [3011711414]
2 3 4 1 2 1
(A) 2/9 (B) 9/2 (C) 0 (D) – 1
[ JEE 2004 (screening)]
Q.14 A unit vector in the plane of the vectors 2î ˆj k̂ , î ĵ k̂ and orthogonal to 5î 2 ĵ 6k̂
6î 5k̂ 3 ĵ k̂ 2î 5k̂ 2 î ĵ 2k̂
(A) (B) (C) (D)
61 10 29 3
[3011711414]
[ JEE 2004 (screening)]
Q.15 If a î j k̂ , a · b 1 and a b ˆj k̂ , then b =
(A) î (B) î ˆj k̂ (C) 2ˆj k̂ (D) 2î [3011711414]
[ JEE 2004 (screening)]
Q.16 Let a , b , c , d are four distinct vectors satisfying a b = c d and a c b d . Show that
a ·b c ·d a ·c b ·d . [3011711465]
[JEE 2004]
Q.17 Let P be the plane passing through (1, 1, 1) and parallel to the lines L1 and L2 having direction ratios
1, 0, –1 and –1, 1, 0 respectively. If A, B and C are the points at which P intersects the coordinate axes,
find the volume of the tetrahedron whose vertices are A, B, C and the origin. [3011711465]
[JEE 2004]
9 8
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.18 A variable plane at a distance of 1 unit from the origin cuts the co-ordinate axes at A, B and C. If the
1 1 1
centroid D (x, y, z) of triangle ABC satisfies the relation 2 2 2 = k, then the value of k is
x y z
(A) 3 (B) 1 (C) 1/3 (D) 9 [3011711516]
[JEE 2005 (Scr)]
Q.19 Find the equation of the plane containing the line 2x – y + z – 3 = 0, 3x + y + z = 5 and at a distance of
1 6 from the point (2, 1, – 1). [3011711516]
[ JEE 2005 (Mains)]
Q.20 Incident ray is along the unit vector v̂ and the reflected ray is along the unit vector ŵ . The normal is
along unit vector â outwards. Express ŵ in terms of â and v̂ .
[3011711516]
9 9
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.26 The number of distinct real values of , for which the vectors 2 î ĵ k̂ , î 2 ĵ k̂ and î ĵ 2 k̂
are coplanar, is [3011711487]
(A) zero (B) one (C) two (D) three [JEE 2007]
Q.27 Let a , b, c be unit vectors such that a b c 0 . Which one of the following is correct?
(A) a b b c c a 0 (B) a b b c c a 0 [3011711538]
(C) a b b c a c 0 (D) a b, b c, c a are mutually perpendicular..
[JEE 2007]
Q.28 Let the vectors P Q , Q R , R S , S T , T U and U P represent the sides of a regular hexagon.
Statement-1: P Q × R S S T 0 [3011711538]
because [JEE 2007]
Statement-2: P Q R S = 0 and P Q S T 0
(A) Statement-1 is true, statement-2 is true; statement-2 is a correct explanation for statement-1.
(B) Statement-1 is true, statement-2 is true; statement-2 is NOT a correct explanation for statement-1.
(C) Statement-1 is true, statement-2 is false.
(D) Statement-1 is false, statement-2 is true.
Q.29 Consider the planes 3x – 6y – 2z = 15 and 2x + y – 2z = 5.
Statement-1: The parametric equations of the line of intersection of the given planes are
x = 3 + 14t, y = 1 + 2t, z = 15t. [3011711589]
[JEE 2007]
Statement-2: The vector 14î 2ˆj 15k̂ is parallel to the line of intersection of given planes.
(A) Statement-1 is true, statement-2 is true; statement-2 is a correct explanation for statement-1.
(B) Statement-1 is true, statement-2 is true; statement-2 is NOT a correct explanation for statement-1.
(C) Statement-1 is true, statement-2 is false.
(D) Statement-1 is false, statement-2 is true.
100
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.31 The edges of a parallelopiped are of unit length and are parallel to non-coplanar unit vectors â , b̂, ĉ
1
such that â · b̂ b̂ · ĉ ĉ · â . Then the volume of the parallelopiped is [3011711691]
2
[JEE 2008]
1 1 3 1
(A) (B) (C) (D)
2 2 2 2 3
Q.32 Let two non-collinear unit vector â and b̂ form an acute angle. A point P moves so that at any time t the
position vector O P (where O is the origin) is given by â cos t b̂ sin t . When P is farthest from origin
O, let M be the length of O P and û be the unit vector along O P . Then, [3011711742]
[JEE 2008]
1 1
â b̂ â b̂
(A) û and M (1 â · b̂) 2 (B) û and M (1 â · b̂) 2
| â b̂ | | â b̂ |
1 1
â b̂ â b̂
(C) û and M (1 2â · b̂) 2 (D) û and M (1 2â · b̂) 2
| â b̂ | | â b̂ |
101
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.36 The distance of the point (1, 1, 1) from the plane passing through the point (–1, –2, –1) and whose
normal is perpendicular to both the lines L1 and L2 is
2 7 13 23
(A) (B) (C) (D) [JEE 2008]
75 75 75 75
Q.37 Let P(3, 2, 6) be a point in space and Q be a point on the line r ( î ĵ 2k̂ ) ( 3î ˆj 5k̂ )
Then the value of for which the vector PQ is parallel to the plane x – 4y + 3z =1 is [3011711861]
(A) 1/4 (B) – 1/4 (C) 1/8 (D) – 1/8
[JEE 2009]
1
Q.38 If a , b, c and d are unit vectors such that a b · c d 1 and a · c , then [3011711912]
2
(A) a , b, c are non-coplanar (B) b, c, d are non-coplanar
(C) b, d are non-parallel (D) a , d are parallel and b, c are parallel
[JEE 2009]
Q.39 A line with positive direction cosines passes through the point P(2, – 1, 2) and makes equal angles with
the coordinate axes. The line meets the plane 2x + y + z = 9 at point Q. The length of the line segment
PQ equals [3011711963]
(A) 1 (B) 2 (C) 3 (D) 2
[JEE 2009]
102
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.40 Match the statements/expressions given in Column I with the values given in Column II.
Column I Column II
(A) Root(s) of the equation 2 sin2 + sin22 = 2 (P)
6
6x 3x
(B) Points of discontinuity of the function f(x) = cos , (Q)
4
where [y] denotes the largest integer less than or equal to y
(C) Volume of the parallelopiped with its edges represented by the vectors (R)
3
î ˆj, î 2ˆj and î ˆj k̂
(D) Angle between vectors a and b where a , b and c are unit (S)
2
vectors satisfying a b 3 c 0 (T)
[3011712014]
[JEE 2009, 8 ]
Q.41 Let (x, y, z) be points with integer coordinates satisfying the system of homogeneous equations :
3x – y – z = 0 ; – 3x + z = 0 ; – 3x + 2y + z = 0 [3011712065]
2 2 2
Then the number of such points for which x + y + z 100 is [JEE 2009, 4]
x y z
Q.42 Equation of the plane containing the straight line and perpendicular to the plane containing
2 3 4
x y z x y z
the straight lines and , is [3011711771]
3 4 2 4 2 3
(A) x + 2y – 2z = 0 (B) 3x + 2y – 2z = 0 (C) x – 2y + z = 0 (D) 5x + 2y – 4z = 0
[JEE 2010, 3]
Q.44 If the distance of the point P(l, – 2, 1) from the plane x + 2y - 2z = , where > 0. is 5, then the foot
of the perpendicular from P to the plane is [3011711873]
8 4 7 4 4 1 1 2 10 2 1 5
(A) , , (B) , , (C) , , (D) , ,
3 3 3 3 3 3 3 3 3 3 3 2
[JEE 2010, 5]
103
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
î 2 ĵ 2î ˆj 3k̂
Q.45 If a and b are vectors in space given by a and b , then the value of
5 14
2a b · a b a 2b , is [3011711924]
[JEE 2010, 3]
x 1 y 2 z 3
Q.46 If the distance between the plane Ax – 2y + z = d and the plane containing the lines
2 3 4
x 2 y 3 z 4
and is 6 , then | d | is [3011711975]
3 4 5
[JEE 2010, 3]
Q.47 Match the statements in Column-I with the values in Column-II. [3011712026]
Column I Column II
(A) A line from the origin meets the lines (p) – 4
8
x
x 2 y 1 z 1 3 y 3 z 1
and
1 2 1 2 1 1
at P and Q respectively. If length PQ = d, then d2 is
1 3
(B) The values of x satisfying tan–1 (x +3) – tan–1 (x – 3) = sin are (q) 0
5
(C) Non-zero vectors a , b and c satisfy a · b 0
b a b c 0 and 2 | b c | | b a | (r) 4
If a b 4c , then the possible values of are
(D) Let f be the function on , given by (s) 5
9x x
f(0) = 9 and f(x) = sin / sin for x 0
2 2
2
The value of
f x dx is
(t) 6
[JEE 2010, (2+2+2+2)]
Q.48 Let a î ĵ k̂ , b î ˆj k̂ and c î ˆj k̂ be three vectors. A vector v in the plane
1
of a and b , whose projection on c is , is given by [3011712077]
3
(A) î 3 ĵ 3k̂ (B) 3î 3 ĵ k̂ (C) 3î ĵ 3k̂ (D) î 3 ĵ 3k̂
[JEE 2011, 3]
Q.49 The vector(s) which is/are coplanar with vectors î ĵ 2k̂ and î 2ˆj k̂ and perpendicular to the
vector î ˆj k̂ is/are [3011711776]
(A) ĵ k̂ (B) î ĵ (C) î ˆj (D) ĵ k̂
[JEE 2011, 4]
104
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.50 Let a î k̂ , b î ĵ and c î 2 ĵ 3k̂ be three given vectors. If r is a vector such that
r b c b and r · a 0 , then the value of r · b , is [3011711827]
[JEE 2011, 4]
Q.51 The point P is the intersection of the straight line joining the points Q (2, 3, 5) and R (1, – 1, 4) with the
plane 5x – 4y – z = 1. If S is the foot of the perpendicular drawn from the point T (2, 1, 4) to QR, then
the length of the line segment PS is [3011712751]
1
(A) (B) 2 (C) 2 (D) 2 2
2
[JEE 2012, 3]
Q.52 The equation of a plane passing through the line of intersection of the planes x + 2y + 3z = 2 and
2
x – y + z = 3 and at a distance from the point (3, 1, – 1) is [3011712753]
3
(A) 5x – 11y + z = 17 (B) 2 x + y = 3 2 – 1
(C) x + y + z = 3 (D) x – 2y=1 – 2 [JEE 2012, 3]
Q.53 If a and b are vectors such that a b 29 and a ( 2î 3ˆj 4k̂ ) = ( 2î 3ˆj 4k̂ ) b , then a
possible value of a b · 7 î 2 ĵ 3k̂ is [3011712702]
(A) 0 (B) 3 (C) 4 (D) 8 [JEE 2012, 3]
x 1 y 1 z x 1 y 1 z
Q.54 If the straight lines and are coplanar, then the plane(s) containing
2 k 2 5 2 k
these two lines is(are) [3011712752]
(A) y + 2z = – 1 (B) y + z = – 1 (C) y – z = – 1 (D) y – 2z = – 1
[JEE 2012, 4]
2 2 2
Q.55 If a , b and c are unit vectors satisfying a b b c c a 9 , then 2a 5b 5c is
[3011712701]
[JEE 2012, 4]
x 2 y 1 z
Q.56 Perpendiculars are drawn from points on the line to the plane x + y + z = 3. The feet
2 1 3
of perpendiculars lie on the line [3011712649]
x y 1 z 2 x y 1 z 2
(A) (B)
5 8 13 2 3 5
x y 1 z 2 x y 1 z 2
(C) (D) [JEE Advance 2013, 2]
4 3 7 2 7 5
105
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Q.57 Let PR = 3î ˆj 2k̂ and SQ = î 3ˆj 4k̂ determine diagonals of a parallelogram PQRS and
PT = î 2 ĵ 3k̂ be another vector. Then the volume of the parallelepiped determined by the vectors
PT, PQ and PS is
(A) 5 (B) 20 (C) 10 (D) 30 [3011712549]
[JEE (Advanced) 2013, 2]
Q.58 A line l passing through the origin is perpendicular to the lines
l1 : (3 t ) î ( 1 2 t ) ĵ ( 4 2t ) k̂ , – < t < [3011712551]
l2 : (3 2s ) î (3 2s) ˆj ( 2 s) k̂ , – < s <
Then, the coordinate(s) of the point(s) on l2 at a distance of 17 from the point of intersection of l and
l1 is (are)
7 7 5 7 7 8
(A) , , (B) (– 1, – 1, 0) (C) (1, 1, 1) (D) , ,
3 3 3 9 9 9
[JEE Advance 2013, 4]
y z y z
Q.59 Two lines L1 : x = 5, = and L2 : x = , = are coplanar. Then can take value(s)
3 2 1 2
(A) 1 (B) 2 (C) 3 (D) 4 [3011712599]
[JEE Advance 2013, 3]
Q.60 Consider the set of eight vectors V a î bĵ ck̂ : a , b, c{1,1} . Three non-coplanar vectors can
be chosen from V in 2p ways. Then p, is [3011712601]
[JEE Advance 2013, 5]
Q.61 Match List-I with List-II and select the correct answer using the code given below the lists:
Column-I Column-II
(A) Volume of parallelepiped determined by vector a , b and c is 2. (P) 100
Then the volume of the parallelepiped determined by vectors
2 a b , 3 b c and c a is
(B) Volume of parallelepiped determined by vectors a , b and c is 5. (Q) 30
Then the volume of the parallelepiped determined by vectors
3 a b , b c and 2 c a is
106
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Q.63 From a point P (, , ), perpendiculars PQ and PR are drawn respectively on the lines y = x, z = 1
and y = – x, z = – 1. If P is such that QPR is a right angle, then the possible value(s) of is(are)
(A) 2 (B) 1 (C) – 1 (D) – 2
[JEE (Advanced) 2014, 3]
Q.64 Let x , y and z be three vectors each of magnitude 2 and the angle between each pair of them is .
3
If a is a nonzero vector perpendicular to x and y z and b is a nonzero vector perpendicular to y
and z x , then
(A) b ( b · z ) ( z x ) (B) a ( a · y) ( y z )
(C) a · b ( a · y) ( b · z) (D) a ( a · y) ( z y) [JEE (Advanced) 2014, 3]
Q.65 Let a , b and c be three non-coplanar unit vectors such that the angle between every pair of them is
p 2 2q 2 r 2
. If a b b c = pa qb rc , where p, q and r are scalars, then the value of is
3 q2
[JEE (Advanced) 2014, 3]
Q.66 In R3, consider the planes P1 : y = 0 and P2 : x + z = 1. Let P3 be a plane, different from P1 and P2,
which passes through the intersection of P1 and P2. If the distance of the point (0, 1, 0) from P3 is 1 and
the distance of a point (, , ) from P3 is 2, then which of the following relations is(are) true?
(A) 2 + + 2 + 2 = 0 (B) 2 – + 2 + 4 = 0
(C) 2 + – 2 – 10 = 0 (D) 2 – + 2 – 8 = 0
[JEE Adv. 2015, 4]
107
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.67 In R3, let L be a straight line passing through the origin. Suppose that all the points on L are at a constant
distance from the two planes P1 : x + 2y – z + 1 = 0 and P2 : 2x – y + z – 1 = 0. Let M be the locus
of the feet of the perpendiculars drawn from the points on L to the plane P1. Which of the following
points lie(s) on M?
5 2 1 1 1 5 1 1 2
(A) 0, , (B) , , (C) , 0, (D) , 0,
6 3 6 3 6 6 6 3 3
[JEE Adv. 2015, 4]
Q.68 Let PQR be a triangle. Let a QR , b RP and c PQ . If | a | = 12, | b | = 4 3 and b · c = 24,
then which of the following is (are) true?
| c |2 | c |2
(A) | a | = 12 (B) | a | = 30
2 2
(C) | a b c a | 48 3 (D) a · b = – 72
[JEE Adv. 2015, 4]
108
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.70 Suppose that p, q and r are three non-coplanar vectors in R3. Let the components of a vector s along
p, q and r be 4, 3 and 5 respectively. If the components of this vector s along
( p q r ), ( p q r ) and ( p, q r ) are x, y and z respectively, then the value of 2x + y + z is
[JEE Adv. 2015, 4]
Q.71 In R2, if the magnitude of the projection vector of the vector î ĵ on 3 î ˆj is 3 and if
=2 + 3 , then possible value(s) of | | is (are)
(A) 1 (B) 2 (C) 3 (D) 4
[JEE Adv. 2015, MTC, 2]
Q.72 Consider a pyramid OPQRS located in the first octant (x 0, y 0, z 0) with O as origin, and OP and
OR along the x-axis and the y-axis, respectively. The base OPQR of the pyramid is a square with
OP = 3. The point S is directly above the mid-point T of diagonal OQ such that TS = 3. Then
(A) the acute angle between OQ and OS is [JEE (Advanced) 2016, 4]
3
(B) the equation of the plane containing the triangle OQS is x – y = 0
3
(C) the length of the perpendicular from P to the plane containing the triangle OQS is
2
15
(D) the perpendicular distance from O to the straight line containing RS is
2
Q.73 Let P be the image of the point (3, 1, 7) with respect to the plane x – y + z = 3. Then the equation of the
x y z
plane passing through P and containing the straight line is [JEE (Advanced) 2016, 3]
1 2 1
(A) x + y – 3z = 0 (B) 3x + z = 0 (C) x – 4y + 7z = 0 (D) 2x – y = 0
1
Q.74 Let û u1î u 2 ĵ u 3k̂ be a unit vector in R3 and ŵ (î ˆj 2k̂ ) . Given that there exists a vector
6
v in R3 such that | û v | 1 and ŵ · (û v) 1 . Which of the following statement(s) is (are) correct ?
(A) There is exactly one choice for such v
(B) There are infinitely many choices for such v
(C) If û lies in the xy-plane then | u1 | = | u2 |
(D) If û lies in the xz-plane then 2| u1 | = | u3 | [JEE (Advanced) 2016, 4]
Q.75 The equation of the plane passing through the point (1, 1, 1) and perpendicular to the planes
2x + y – 2z = 5 and 3x – 6y – 2z = 7, is
(A) – 14x + 2y + 15z = 3 (B) 14x + 2y – 15z = 1
(C) 14x + 2y + 15z = 31 (D) 14x – 2y + 15z = 27
[JEE (Advanced) 2017, 3]
109
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
Q.76 Let O be the origin and let PQR be an arbitrary triangle. The point S is such that
OP · OQ OR · OS = OR · OP OQ · OS = OQ · OR OP · OS .
Then the triangle PQR has S as its
(A) circumcentre (B) orthocenter (C) incentre (D) centroid
[JEE (Advanced) 2017, 3]
Q.78 If the triangle PQR varies, then the minimum value of cos (P + Q) + cos (Q + R) + cos (R + P) is
3 5 3 5
(A) (B) (C) (D)
2 3 2 3
[JEE (Advanced) 2017, 3]
110
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
[RANK BOOSTER]
VECTOR
[ SINGLE CORRECT CHOICE T Y PE]
Q.1 Four vectors a , b, c and x satisfy the relation (a · x ) b c x where b · a 1 . The value of x in terms
of a , b and c is equal to
c
(a · c )b c(a · b 1)
(A) (B)
(a · b 1) a · b 1
2( a · c ) b c 2( a · c ) c c
(C) (D)
a · b 1 a · b 1
Q.2 If a and b are two non-zero vectors, then the value of scalar [(a b) a ] · [( b a ) b] equals
(A) | b | 2 | a b | 2 (B) (a · b) | a b | 2 (C) a 2 | a b | 2 (D) (a · b) | a b | 2
Q.3 a , b, c are three coplanar unit vectors such that a b c = 0. If three vectors p, q, r parallel to
a , b, c respectively and having integral but different magnitudes, then among the following options
p q r can take a value equal to
[ PARAGRAPH T Y PE]
Paragraph for question nos. 5 to 7
Let OABC be a regular tetrahedron with side length unity. Angle between skew lines OA & BC be ,
angle between skew lines OB & CA be and angle between skew lines OC & AB be .
Q.5 sin2 + sin2 + sin2 is equal to
3 9
(A) 0 (B) (C) (D) 3
4 4
Q.6 Volume of tetrahedron is equal to
1 1 1 1
(A) (B) (C) (D)
2 3 2 6 2 12
Q.7 Let foot of perpendicular from vertex O on plane face ABC be N then AN is equal to
1 2 2 1
(A) (B) (C) (D)
3 3 3 6
111
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
1 1 1 2 2 1 2 2
(A) , (B) , (C) , (D) ,
3 3 3 3 3 3 3 3
Q.10 For real numbers x, y the vector p xa yc satisfies the condition 0 p · a 1 and 0 p · b 1. The
maximum value of p · c is equal to
1
(A) 1 (B) 3 (C) 3 (D)
3
Q.11 For the maximum value of x and y, the linear combination of p in terms of a and b is equal to
(A) a 2b (B) 2a b (C) 2 (a b) (D) 3a 2b
Q.12 If a , b are non-parallel unit vectors and c is a vector in a plane perpendicular to a and b such that
2
c = 5 and a b = a b then
3 3
(A) a · b = (B) a · b = (C) [a b c] = – 4 (D) [a b c] = 4
5 5
3 cos sin
Q.13 If a = 3 sin î cos ˆj and b = î ˆj represents diagonals of a parallelogram
3 2 cos 2 3 2 cos 2
3
such that area of the parallelogram is less than or equal to then
10
3
(A) a · b = (B) a · b = 0
5
9 9
(C) [a b a b] = (D) [a b a b] =
100 25
112
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Q.15 Let a and b be unit vectors and angle between them is . If a · b and a b are the two roots of
1 1
the cubic equation x3 –
2 1 x2 + 2 x – = 0, then
2 2
List-I List-II
1 1
(A) 2 2 is equal to (P) 0
(a · b ) ab
(B) if is the area of the triangle whose sides are represented by (Q) 1
1
a & b and 2 is the angle between them, then is equal to
(C) third root of the equation is (R) 2
| a b |
2
(D) sin
x dx is equal to (S) 4
a·b
[ INT EGER
T YPE]
Q.16 Let a 3 dimensional vector V satisfies the condition, 2V V ( î 2 ĵ) = 2î k̂ .
If 3 V = m where m N, then find m. [3011711674]
Q.17 Let a x 2 î 3 ĵ ( x 3) k̂ and b î 3 ĵ ( x 3) k̂ be two vectors such that | a | = | b | .
3
v1
If v1 2a 3b & v 2 3a 2b and I = v 2 dx , then find the value of [I].
1
[Note: [k] denotes greatest integer function less than or equal to k.]
113
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3 - D I M E N S I O N A L G E O M E T RY
[ SINGLE CORRECT CHOICE T Y PE]
Q.1 If acute angle between the line r = î 2 ĵ ( 4î 3k̂ ) and xy plane is and acute angle between the
planes x + 2y = 0 and 2x + y = 0 is then (cos2 + sin2) equals
1 2 3
(A) 1 (B) (C) (D)
4 3 4
Q.2 The point of intersection of the plane r · (3î 5ˆj 2k̂ ) 6 with the straight line passing through the
origin and perpendicular to the plane 2x – y – z = 4, is (x0, y0, z0). The value of (2x0 – 3y0 + z0), is
(A) 0 (B) 2 (C) 3 (D) 4
Q.3 Let be the plane containing the line x + y – z – 1 = 0 = x + 4y + 3z and parallel to the line
6(x – 1) = 3y = 2(z + 1). The perpendicular distance of the plane from origin is
1 1 1
(A) 1 (B) (C) (D)
2 3 6
[ PARAGRAPH T Y PE]
Paragraph for question nos. 5 to 7
Let r1 a 2 î 2b ˆj 6 k̂ and r2 2a î a ĵ a 2 k̂ be non-zero vectors and r3 î 2ˆj a k̂ be a
position vector of a point where a, b R. P1 and P2 are two planes for the largest integral value of b,
which containing vector r1 and r2 is the normal vector of both the planes and passing through point r3 .
Q.6 If d1 and d2 are perpendicular distances of the planes from the origin then (d1 + d2) equals
5 7 3
(A) 0 (B) (C) (D)
6 6 6 6
Q.7 Equation of the plane containing the line P1 = 0 = P2 and passing through the origin is
(A) 2x – y + 2z = 0 (B) 2x + y – z = 0 (C) 2x + y – 2z = 0 (D) x + y – 2z = 0
114
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x2 y 1 z 1
Q.10 The line = = intersects the curve x2 – y2 = a2, z = 0 if a is equal to
3 2 1
(A) 4 (B) 5 (C) –4 (D) 5
115
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
x 1 y 2 z 3 x 2 y 3 z 4
Q.12 Let L1 : = = and L2 : = = be two lines.
2 3 4 3 4 6
List-I List-II
(A) If plane containing line L1 and parallel to line (P) 3
L2 is ax + by – z + d = 0, then (a + b + d) equals
(B) If is the shortest distance between both the lines (Q) 2
1
then 2 equals
1
(C) If P1 is the plane containing L1 and parallel to L2 and P2 (R)
5
is the plane containing L2 and parallel to L1 , then distance
between both the planes, is
(D) If vector along the shortest distance of both the lines is (S) 5
pî q ˆj k̂ , then (p + q) equals
Code :
(A) (B) (C) (D)
(A) Q P S R
(B) P S P Q
(C) Q S R P
(D) P S R Q
Q.13 Consider a plane passing through three points A(a, 0, 0), B(0, b, 0), C(0, 0, c) with a > 0, b > 0, c > 0.
Let d be the distance between the origin O and the plane and m be the distance between the
origin O and the point M(a, b, c). If a, b, c vary in the range of any positive numbers, then find the
2
m
minimum value of . [3011711667]
d
x y z
Q.14 Line L meets lines L1 : and L2 : x 2 y 1 z 4 orthogonally at points P and Q.
1 2 3 2 4 5
5D
(PQ)2 is D. DRs of line L are (a, b, c) {a, b, c I}, then least value of a b c .
3
Q.15 Let equation of plane be x + 2y + z – 3 = 0. An insect starts flying from point P(1, 3, 2) in straight line.
It touches the plane at point R(a, b, c) and then goes to point Q(3, 5, 2) in straight line. If distance
travelled PR + QR is minimum then find the value of (a + b + c).
Q.16 Let the lines
L1 : r = (7 î + 6 ˆj + 2 k̂ ) + (–3 î + 2 ˆj + 4 k̂ )
L2 : r = (5 î + 3 ˆj + 4 k̂ ) + (2 î + ˆj + 3 k̂ )
116
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
ANSWER KEY
EXERCISE-1
SECTION-A
5 1 2 27
Q.1 Q.3 cos–1 Q.4 Q.5
2 3 3 2
1
Q.7 5î 10ˆj 10k̂ Q.8
1
Q.9
4
d î ˆj k̂
2
1 1 1 2 2 1
Q.10 0 Q.11 ± ,± ,± Q.12 î ˆj k̂
3 3 3 3 3 3
Q.13 1 Q.14
p 2 32î ĵ 14k̂ Q.15 4 Q.16 5b
1
Q.17 p = – Q.18 –10
3
Q.19 Show that the four points A, B, C and D with position vectors 4iˆ 5jˆ k,
ˆ ˆj k,3
ˆ ˆi 9 ˆj 4 kˆ and
4( ˆi ˆj k)
ˆ respectively are coplanar..
Q.20 =1 Q.21
ˆi 11jˆ 7kˆ Q.22 = – 9, µ = 27
1 1
Q.23
7
6î 3 ĵ 2k̂ Q.24
2
210 sq. unit Q.26 19 2
11 ˆ
Q.27 3î j 5k̂ Q.28 1 Q.29 5 2
3
21
Q.30 = Q.31 15 2 sq. units
2
Q.33 Show that the pointsA ( 2î 3 ĵ 5k̂ ) , B ( î 2ˆj 3k̂ ) and C (7î k̂ ) are collinear..
1
Q.34 If a and b are unit vectors and is the angle between them, then prove that cos = | a b |.
2 2
4
Q.35 91 cubic units Q.36 7 ( î ĵ k̂ ) Q.37
5
8
Q.41 y = 3 or y = – 1 Q.42 75 Q.43 sin 1
21
3 2 8 19
Q.44 , , Q.45 cos 1 Q.46 A (5î 4 ĵ 6k̂ ) (3î 7 ĵ 2k̂ )
77 77 77 21
117
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
13 23
Q.47 , , 0
5 5
Q.48
r 3î 4 ĵ 3k̂ 5î 7ˆj 2k̂ Q.49 90º
5 7
Q.50 Q.52 –1 Q.53 7x – 5y + 4z – 8 = 0 Q.54 1,
2 3
Q.55 r .( 20î 23 ĵ 26k̂ ) 69 Q.57 17
3 2x 2 y z 3
Q.58 (i) ; (ii) = 1; (iii) 0, , 0 ; (iv) x = 2t + 2 ; y = 2t + 1 and z = – t + 3
2 3 3 3 2
SECTION-B
VECTOR
Q.1 A Q.2 D Q.3 A Q.4 C Q.5 B
Q.6 A Q.7 B Q.8 D Q.9 A Q.10 B
Q.11 A Q.12 D Q.13 C Q.14 C Q.15 C
Q.16 D Q.17 C Q.18 C Q.19 A Q.20 C
Q.21 C Q.22 A Q.23 A Q.24 D Q.25 C
3-DIMEN SIONAL G E O M E T RY
Q.1 C Q.2 A Q.3 B Q.4 B Q.5 C
Q.6 D Q.7 D Q.8 B Q.9 B Q.10 B
Q.11 C Q.12 B Q.13 D Q.14 C Q.15 B
Q.16 A Q.17 A Q.18 A Q.19 B Q.20 A
EXERCISE-2
VECTOR
Q.1 A Q.2 B Q.3 C Q.4 D Q.5 D
Q.6 B Q.7 D Q.8 C Q.9 C Q.10 B
Q.11 A Q.12 B Q.13 C Q.14 A Q.15 A
Q.16 D Q.17 ABD Q.18 ABC Q.19 ABD
Q.20 (A) T; (B) U ; (C) P ; (D) R ; (E) Q; (F) S; (G) W; (H) V Q.21 (A) S; (B) P; (C) R; (D) Q
Q.22 (A) Q; (B) S; (C) R; (D) Q; (E) P Q.23 35 Q.24 5 Q.25 34
Q.26 48 Q.27 5 Q.28 51 Q.29 13 Q.30 1125
( 1) n
Q.31 488 Q.32 13 Q.33 n , n I & 1
2
1
Q.34 (î 5 ĵ k̂ )
3 3
118
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3-DIMEN SIONAL G E O M E T RY
Q.1 A Q.2 D Q.3 D Q.4 D Q.5 B
Q.6 A Q.7 A Q.8 A Q.9 D Q.10 B
Q.11 C Q.12 A Q.13 C Q.14 B Q.15 C
Q.16 D Q.17 D Q.18 ABC Q.19 BD Q.20 AC
Q.21 (A) R ; (B) Q, (C) Q, S, (D) P, S Q.22 240 Q.23 7 Q.24 23
Q.25 12 Q.26 7/5 Q.27 x – 8y + 7z = 2
x 7 y2 z 1 2
Q.28 2x + 3y + z + 4 = 0 Q.29 Q.30
22 5 4 3
EXERCISE-3
EXERCISE-4
Q.2 v 1 2i , v 2 i j, v 3 3i 2j 4k Q.3 B Q.4 C
Q.24 (A) Q, R; (B) P, (C) S, (D) P Q.25 (A) Q, (B) Q, (C) R, (D) P Q.26 C
Q.27 B Q.28 C Q.29 D Q.30 (A) R; (B) Q; (C) P; (D) S
Q.31 A Q.32 AC Q.33 D Q.34 B Q.35 D
Q.36 C Q.37 A Q.38 C Q.39 C
Q.40 (A) Q, S ; (B) P, R, S, T ; (C) T ; (D) R Q.41 7 Q.42 C
Q.43 B Q.44 A Q.45 5 Q.46 6
119
VE CT OR & 3 -DIM ENS IONA L GE OMET RY
EXERCISE-5
VECTOR
Q.1 A Q.2 B Q.3 C Q.4 A Q.5 D
Q.6 C Q.7 A Q.8 C Q.9 B Q.10 B
Q.11 C Q.12 BCD Q.13 BD
Q.14 (A) Q ; (B) R, S ; (C) R, S ; (D) P Q.15 (A) S ; (B) R ; (C) Q ; (D) P Q.16 6
Q.17 3
3 - D I M E N S I O N A L G E O M E T RY
Q.1 A Q.2 D Q.3 C Q.4 A Q.5 B
Q.6 D Q.7 A Q.8 BC Q.9 ABCD Q.10 AC
Q.11 (A) R ; (B) Q ; (C) S ; (D) P Q.12 (A) ; P (B) ; S (C) ; R (D) ; Q Q.13 9
Q.14 6 Q.15 2 Q.16 9
120