DOCmaths
DOCmaths
SECTION A
This section comprises multiple choice questions (MCQs) of 1 mark each.
1. If x = at, y a , dy
is :
= dx
then
t
(A) t2 (B) – t2
(C) 1 1
(D) –
t2 t2
2. The solution of the differential dy 1 is
equation : log y
=
dx
(A) log y = x + c (B) y log y – y = x + c
(C) log y – y = x + c (D) y log y + y = x + c
3. The vector with terminal point A (2, – 3, 5) and initial point B (3, –
4, 7) is :
^ ^ ^ ^ ^
(A) i – j +2 (B) i + j +2k
^ ^ ^ ^
k (D) – i + j – 2 k
^ ^
(C) – i – j –
^
2k
f(x) ìï x 2 + 3, x s ?
= 0í
ïî 1 , x =
0
(A) f(x) is continuous and differentiable ∀ x ϵ ℝ
(B) f(x) is continuous ∀ x ϵ ℝ
(C) f(x) is continuous and differentiable ∀ x ϵ ℝ – {0}
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(D) f(x) is discontinuous at infinitely many points
∫ 0
π/ 2
π/
2
(C)
(D)
2
∫ f (x) 2
∫
0
cos3 x dx
dx
0
(A) ± 3 3
(B) ±
5 4
(C) ±
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4 4
(D) ±
5 3
8. The integrating factor of the differential equation (1 dy
+ xy = ax,
– x 2) dx
– 1 < x < 1, is :
(A) 1 1
(B)
x2 – 1
x2 –
(C) 1 11
(D)
2 2
1–x 1–x
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3 3
If the direction cosines of a line 3 k, k, k, then the value of k
are is :
(E) ±1 (B) ± 3
1
(C) ±3 (D) ±
3
(C) P(A 3 B) 1
= P(B) (D) P(A 3 B) = 2 P(B)
2
x +1 x–1
9. is equal to :
2 2
x +x +1 x – x +
1
(A) 2x3 (B) 2
(C) 0 (D) 2x3 –
2
(A) Both Assertion (A) and Reason (R) are true and Reason (R) is
the correct explanation of the Assertion (A).
(B) Both Assertion (A) and Reason (R) are true, but Reason (R) is not
the correct explanation of the Assertion (A).
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「 1 cos θ 1 ù
9. Assertion (A) : For matrix A | |
|– cos θ 1 cos θ| , where θ ∊ [0, 2π],
=
|L – – cos 1 |]
|A| ∊ [2, 1 θ
4].
Reason (R) : cos θ ∊ [– 1, 1], ∀ θ ∊ [0, 2p].
Reason (R) : For any line making angles, α, β, y with the positive
directions of x, y and z axes
respectively, cos2 α + cos2 β + cos2 y = 1.
SECTION B
This section comprises very short answer (VSA) type questions of 2 marks each.
→
11. In the given figure, ABCD is a parallelogram. If = 2 ^i – 4 ^j and
AB
^
+5k
→ ^ ^ ^
DB = 3 i – 6 j + 2 k , then AD and hence find the area of
→
find
parallelogram ABCD.
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10. (a) Check the differentiability of function f(x) = [x] at x = – 3,
11. Find local maximum value and local minimum value (whichever exists)
for the function f(x) = 1
(x s 0).
2
4x + x
1+
∫ x 2x dx
OR
(b) Evaluate
:
π2 sin x
dx
∫
4
0 x
→ → →
13. If → and are two non-zero vectors such that →
+ ) z
( and
a b a b a
(2 + ) z → , then prove that |→ | =
→ → | → |.
a b b b 2 a
SECTION C
This section comprises short answer (SA) type questions of 3 marks each.
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12. –
E and F are two independent events such that P( E ) = 0·6 and
– –
E 4F ).
P(E 4 F) = 0·6. Find P(F) and P(
OR
14. (a) If 2
1– 1–y
+ 1– = a (x – y), prove dy
x
2
y
2
that dx = 1 – x2 .
OR
9)
OR
(b) Evaluate :
3
∫ 1
(|x – 1|+|x – 2|+|x – 3|) dx
(tan–1 y – x) dy = (1 + y2) dx
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SECTION D
This section comprises long answer type questions (LA) of 5 marks each.
15. Find the equation of a line l2 which is the mirror image of the line l1 with
z–2
respect to line l : y– = , given that line l passes through the
x =
1 3
1
2
1
point P(1, 6, 3) and parallel to line l.
「1 – 0ù
16. (a) If 2 |
– 1 , find A–1 and use it to solve the following
| |
A= 2 –1
| 1 |]
|L 0 – 2
system of equations :
x – 2y = 10, 2x – y – z = 8, – 2y + z = 7
OR
「– 1 a 2ù 「 1 –1 1ù
(b) If | x| | |
A = | 1 2 | and A–1 = |– 8 7 – 5| ,
|L 3 1 |L b y 3 |]
1|]
OR
(b) Evaluate
: 3
2 x +|x|+ 1
∫ 2
x + 4|x|+ 4
dx
–2
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2
2 y
18. Using integration, find the area of the x = 1, included
4
+
ellipse between the lines x = – 2 and x = 2. 16
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Case Study – 1
2
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666
OR
(iii) (b) Find the domain and range of f(x) = 2 sin–1 (1 – x). 2
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Case Study –
2
19. The traffic police has installed Over Speed Violation Detection
(OSVD) system at various locations in a city. These cameras can
capture a speeding vehicle from a distance of 300 m and even
function in the dark.
(ii) Find
dθ
. 1
dx
(iii) (a) Find the rate of change of angle of elevation with respect
to time at an instant when the car is 50 m away from the
pole. 2
OR
of the pole
3
is rad/s, then find the speed of the car. 2
101
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Case Study –
2
(i) Find the probability that an airplane reached its destination late. 2
(ii) If the airplane reached its destination late, find the probability
that it was due to moderate turbulence. 2
1 You are aware that evaluation is the most important process in the actual and correct
assessment of the candidates. A small mistake in evaluation may lead to serious problems
which may affect the future of the candidates, education system and teaching profession.
To avoid mistakes, it is requested that before starting evaluation, you must read and
understand the spot evaluation guidelines carefully.
2 “Evaluation policy is a confidential policy as it is related to the confidentiality of the
examinations conducted, Evaluation done and several other aspects. Its’ leakage to
public in any manner could lead to derailment of the examination system and affect
the life and future of millions of candidates. Sharing this policy/document to anyone,
publishing in any magazine and printing in News Paper/Website etc may invite
action under various rules of the Board and IPC.”
3 Evaluation is to be done as per instructions provided in the Marking Scheme. It should not
be done according to one’s own interpretation or any other consideration. Marking
Scheme should be strictly adhered to and religiously followed. However, while
evaluating, answers which are based on latest information or knowledge and/or are
innovative, they may be assessed for their correctness otherwise and due marks be
awarded to them.
4 The Marking scheme carries only suggested value points for the answers
These are in the nature of Guidelines only and do not constitute the complete answer. The
students can have their own expression and if the expression is correct, the due marks
should be awarded accordingly.
5 The Head-Examiner must go through the first five answer books evaluated by each
evaluator on the first day, to ensure that evaluation has been carried out as per the
instructions given in the Marking Scheme. If there is any variation, the same should be
zero after deliberation and discussion. The remaining answer books meant for evaluation
shall be given only after ensuring that there is no significant variation in the marking of
individual evaluators.
6 Evaluators will mark( √ ) wherever answer is correct. For wrong answer CROSS ‘X” be
marked. Evaluators will not put right (✓)while evaluating which gives an impression that
answer is correct and no marks are awarded. This is most common mistake which
evaluators are committing.
7 If a question has parts, please award marks on the right-hand side for each part. Marks
65 /1/3 24 P.T.O.
awarded for different parts of the question should then be totaled up and written in the left-
hand margin and encircled. This may be followed strictly.
8 If a question does not have any parts, marks must be awarded in the left-hand margin and
encircled. This may also be followed strictly.
9 In Q1-Q20, if a candidate attempts the question more than once (without canceling the
previous attempt), marks shall be awarded for the first attempt only and the other answer
scored out `with a note “Extra Question”.
10 In Q21-Q38, if a student has attempted an extra question, answer of the question deserving
more marks should be retained and the other answer scored out with a note “Extra
Question”.
11 No marks to be deducted for the cumulative effect of an error. It should be penalized only once.
65 /1/3 2 P.T.O.
666
Case Study –
3
65 /1/3 3 P.T.O.
17 The Examiners should acquaint themselves with the guidelines given in the “Guidelines
for spot Evaluation” before starting the actual evaluation.
18 Every Examiner shall also ensure that all the answers are evaluated, marks carried over to
the title page, correctly totaled and written in figures and words.
19 The candidates are entitled to obtain photocopy of the Answer Book on request on payment
of the prescribed processing fee. All Examiners/Additional Head Examiners/Head
Examiners are once again reminded that they must ensure that evaluation is carried out
strictly as per value points for each answer as given in the Marking Scheme.
65 /1/3 4 P.T.O.
MARKING SCHEME
MATHEMATICS (Subject Code–041)
(PAPER CODE: 65/1/3)
1.
Ans (D) −1
𝑡2
1
2.
3.
5.
Ans (C) 2 1
65 /1/3 4 P.T.O.
6.
Ans (D) 3 x 3 1
7.
8.
Ans (D) 9 1
9.
10.
11.
Ans (D) 18 1
65 /1/3 5 P.T.O.
12.
Ans (B) 0 1
13.
𝟒
(C) ±
𝟓
Ans 1
14.
𝟏
√𝟏− 𝒙𝟐
Ans (D) 1
15.
𝟏
(D) ±
𝟑
Ans 1
16.
65 /1/3 6 P.T.O.
Ans (B) linear function 1
17.
𝟏
(C) P(A ∩ 𝑩) = 𝑷 (𝑩)
𝟐
Ans 1
18.
Ans (B) 2 1
19.
Ans (A) Both Assertion (A) and Reason (R) are true and the Reason (R) is the correct explanation of 1
Assertion (A).
20.
Ans (A) Both Assertion (A) and Reason (R) are true and the Reason (R) is the correct explanation of 1
Assertion (A).
SECTION-B
(Question nos. 21 to 25 are very short Answer type questions carrying 2 marks each)
65 /1/3 7 P.T.O.
21.
22(a).
RHD = lim
𝑓(−3+ℎ)
−𝑓(−3) ℎ→0 ℎ
𝟏
𝟐
= ℎ→0
lim =0
−3−(−3)
ℎ
lim
𝑓(−3−ℎ)−𝑓(−3)
LHD = ℎ→0 −ℎ
= lim ( )
= lim
−4−(−3) −1
ℎ→0 ℎ ℎ→0 ℎ 𝟏
𝟐
𝟏
= not defined
∵ LHD ≠ RHD 𝟐
𝟏
So f is not differentiable at x = −3
𝟐
OR
22(b).
65 /1/3 8 P.T.O.
65 /1/3 9 P.T.O.
−𝟐 −𝟐
𝒙𝟑 + 𝒚 =𝟎
𝟏 𝟏 𝒅𝒚
𝟑
Ans
𝟑 𝟑 𝒅𝒙
−𝟐
𝟏
𝒅𝒚 −𝒙𝟑 𝟏
𝒅𝒙 −𝟐 𝟐
𝒚𝟑
=
𝒅𝒚 −𝟒
( 𝒙) = = −𝟏 𝟏
𝒅 (𝟏 ,𝟏 ) 𝟒
𝟖 𝟖 𝟐
23.
f(x) = 4 𝑥2 + ( x ≠ 0)
1
𝑥
Ans
𝑓′ (x) = 8x −
1
=0 1
𝑥2
2
⇒ 𝑥 = ⇒𝑥 =
3 1 1
1
8 2
2
𝑓 ( 𝑥) = 8 + > 0 at x =
′′ 2 1
1
𝑥3 2
2
∴ Local minimum value = f ( ) = 3 1
1
2
2
24(a).
1 + 2x = 𝒕𝟐 𝟏
2 𝒅𝒙 = 2t 𝒅𝒕 𝟐
Sol.
− +𝑪
( 𝟏+𝟐𝒙)𝟐 ( 𝟏+𝟐𝒙)𝟐
= 𝟏𝟎 𝟔 𝟐
OR
24(b).
𝝅𝟐𝒔𝒊𝒏√𝒙
∫𝟎𝟒 𝒅𝒙 Put √𝒙 = 𝒕 ⇒ 𝒅𝒙 = 𝟐𝒕 𝒅𝒕
Sol.
𝟏
√𝒙
𝟐
2 ∫ 𝐬𝐢𝐧 𝒕 𝒅𝒕 = 𝟐 [− 𝐜𝐨𝐬 𝒕]𝟐
𝝅 𝝅
𝟐
𝟎 𝟎
𝟏
65 /1/3 1 P.T.O.
0
65 /1/3 1 P.T.O.
1
𝟏
=2 𝟐
25.
26.
Ans Min z = 5 x -2 y
Correct
graph-
𝟏𝟐
𝟏
𝟏
A(60, 0) 300 table-
B(40, 20) 160
C( 60, 30) 240
D(120, 0) 600
𝟏
Min Z = 160 at x = 40, y = 20 𝟐
65 /1/3 10 P.T.O.
27.
28(a).
𝟐
Let (x,y) ∈ 𝑹 for some x,y ∈ A
(b)Symmetric:
OR
28(b).
𝟏
Ans f(x) = ax + b
= −1 f(x) = 2 x – 1
Solving a+ b = 1 and 2a + b = 3 to get a=2 , b
⇒ x = 𝒚+𝟏 ∈ 𝑹 (domain)
𝟐
Also, f(x) = f (𝒚+𝟏) = y
𝟐
∴ f is onto. 𝟏
29(a).
65 /1/3 11 P.T.O.
65 /1/3 12 P.T.O.
Ans √𝟏 − 𝒙𝟐 + √𝟏 − 𝒚𝟐 = 𝒂(𝒙 − 𝒚)
𝟏
Put x = sin 𝜽 , y = sin 𝝓
𝟐
⇒ cos 𝜽 + cos 𝝓 = a (sin 𝜽 – sin 𝝓 )
⇒ 2 cos (𝜽+ 𝝓) cos (𝜽− 𝝓) = 2 a sin (𝜽− 𝝓) cos (𝜽+ 𝝓) 𝟏
𝟐 𝟐 𝟐 𝟐
𝟐
⇒ cot (𝜽− 𝝓) = a
𝟐
⇒ 𝜽 − 𝝓 = 2 𝐜𝐨𝐭−𝟏 𝒂
⇒ 𝐬𝐢𝐧−𝟏 𝒙 − 𝐬𝐢𝐧−𝟏 𝒚 = 𝟐 𝐜𝐨𝐭−𝟏 𝒂 𝟏
𝟐
⇒ √𝟏− 𝒙𝟐− √𝟏− 𝒚𝟐 𝒅𝒙=
𝟏 𝟏 𝒅𝒚
𝟏
0
√ 𝒙𝟐
𝟏
⇒ 𝒅𝒙 = 𝟏−
𝒅𝒚 𝟏− 𝒚𝟐
𝟐
OR
y = (𝐭𝐚𝐧 𝒙)𝒙
29(b).
𝟏
Ans
𝟐
log y = x log (tan x)
𝟐
=( x 𝐭𝐚𝐧
) + 𝐥𝐨𝐠(𝐭𝐚𝐧 𝒙)
𝟏 𝒅𝒚 𝒔𝒆𝒄 𝒙
𝒚 𝒅𝒙 𝒙 𝟐
𝒙 𝒔𝒆𝒄𝟐𝒙
= (𝐭𝐚𝐧 𝒙) [ + 𝐥𝐨𝐠(𝐭𝐚𝐧 𝒙)]
( )
𝒅𝒚 𝒙
𝒅𝒙 𝐭𝐚𝐧 𝒙 𝟏
𝟐
30(a).
𝒅𝒙
𝒙𝟐
Sol. Let I = ∫
(𝒙𝟐+𝟒)(𝒙𝟐+𝟗) 𝟏
𝟐
Put 𝒙𝟐 = 𝒕
= + ⇒A=
𝒕 𝑨 𝑩 −𝟒
𝟗
(𝒕+𝟒)(𝒕+𝟗) 𝒕+ 𝟒 𝒕+𝟗
, B
𝟓 𝟓
=
𝟏
𝟏
I = −𝟒 ∫ 𝒅𝒙 + 𝒅𝒙
𝟏 𝟗 𝟏
∫ 𝟐
𝟓 𝟐𝟐+ 𝒙𝟐 𝟓 𝟑𝟐+ 𝒙𝟐
−𝟐 𝒙 𝟑
𝐭𝐚𝐧−𝟏 ( ) + 𝐭𝐚𝐧−𝟏 ( ) + 𝑪
𝒙
𝟏
𝟓 𝟐 𝟓 𝟑
=
OR
30(b).
𝟑
∫𝟏 𝟑(|𝒙 − 𝟏| + |𝒙 − 𝟐
𝟐 | + |𝒙 − 𝟑|)𝒅𝒙
Ans
𝟑 𝟑 𝟏
= ∫ ( 𝒙 − 𝟏)𝒅𝒙 + ∫ −(𝒙 − 𝟐)𝒅𝒙(+ ∫ 𝒙 − 𝟐)𝒅𝒙( − ∫ 𝒙 − 𝟑)𝒅𝒙 𝟏
𝟏 𝟏 𝟐 𝟏 𝟐
65 /1/3 12 P.T.O.
65 /1/3 13 P.T.O.
= ∫ 𝟐 𝒅𝒙 + ∫ (𝟐 − 𝒙) 𝒅𝒙 + ∫ (𝒙 − 𝟐)𝒅𝒙
𝟑 𝟐 𝟑
𝟏 𝟏 𝟐
𝟐 𝟐 𝟐 𝟑
= [𝟐𝒙] + [ ] + [ ]
𝟑 (𝟐−𝒙) (𝒙−𝟐)
𝟏 −𝟐 𝟐
𝟏 𝟐 𝟏
+
𝟏 𝟏 𝟏
𝟐
𝟐 𝟐
=4+ = 5
31.
𝟏
+1+ 𝑦2 𝑥 = 1+ 𝑦2
𝑑𝑥 1 tan−1 𝑦
𝑑𝑦
1
1
∫ 𝑑𝑦
I. F = 𝑒 = 𝑒tan 𝑦
−1
1+ 𝑦2
2
𝟏
−1
𝑥 × 𝑒 ∫ 𝑦2 𝑒tan 𝑑𝑦
tan−1 𝑦 tan 𝑦 −1
𝑦
= 1+
1
⇒ 𝑥𝑒tan 𝑦
= (tan−1 𝑦) 𝑒tan 𝑦
− 𝑒tan 𝑦
+𝐶
−1 −1 −1
2
OR
⇒ 𝑥 = tan−1 𝑦 − 1 + 𝐶 𝑒− 𝑦
−1
tan
SECTION-D
(Question nos. 32 to 35 are Long Answer type questions carrying 5 marks each)
32.
𝑦−1 𝑧−2
D ratios of the line 𝑙 i.e. 𝑥 = = 1
1 2 3 2
Sol. are 1, 2, 3
1
Let coordinates of foot of perpendicular M on line 𝑙 be (𝜆, 2𝜆 + 1, 3𝜆 + 2) 2
D.ratios of PM are 𝜆 − 1, 2𝜆 − 5, 3𝜆 − 1 1
2
1 (𝜆 − 1) + 2 (2𝜆 − 5) + 3(3𝜆 − 1) = 0 (∵ PM ⊥ 𝑙) 1
2
⇒ 𝜆=1 1
2
Coordinates of M are (1, 3, 5) 1
65 /1/3 14 P.T.O.
𝑧−7
Equation of line 2𝑙 is 𝑥−1 = 𝑦 =
1 2 3 1
2
33(a).
𝑨𝒅𝒋 𝑨 = [−𝟐 𝟏 𝟐
𝟏]
−𝟒 𝟐 𝟑 𝟏
−𝟑 𝟐 𝟐
𝑨−𝟏 = [−𝟐 𝟏 𝟐
𝟏]
−𝟒 𝟐 𝟑
𝟏 −𝟐 𝟎 𝒙 𝟏𝟎
AX = B ⇒ [𝟐 −𝟏 −𝟏] [𝒚] = [ 𝟏
𝟏
𝟖] 𝟐
𝟎 −𝟐 𝟏 𝒛 𝟕
𝒙 −𝟑 𝟐 𝟐 𝟏𝟎 𝟎
𝒚
X = 𝑨−𝟏𝑩 ⇒ [ ] = [−𝟐 𝟏 𝟏] [
𝟖 ] = [−𝟓]
𝒛 −𝟒 𝟐 𝟑 𝟕 −𝟑
⇒ 𝒙 = 𝟎, 𝒚 = −𝟓, 𝒛 = −𝟑
OR
33(b).
Ans 𝑨𝑨−𝟏 = 𝑰 𝟏
−𝟏 𝒂 𝟐 𝟏 −𝟏 𝟏 𝟏 𝟎 𝟎
[ 𝟏 𝟐 𝒙] [−𝟖 𝟕 −𝟓] =
[𝟎 𝟏 𝟎]
𝟑 𝟏 𝟏 𝒃 𝒚 𝟑 𝟎 𝟎 𝟏 𝟏
−𝟏 − 𝟖𝒂 + 𝟐𝒃 𝟏 + 𝟕𝒂 + 𝟐𝒚 𝟓 − 𝟓𝒂 𝟏
𝟐
𝟏 𝟎𝟎 [ −𝟏𝟓 + 𝒃𝒙 𝟏𝟑 +
𝒙𝒚 𝟑𝒙 − 𝟗] = [𝟎 𝟏 𝟎] 𝟏
−𝟓 + 𝒃 𝟒+𝒚 𝟏 𝟎 𝟎 𝟏
𝟏
-5 + b = 0 ⇒ 𝒃 = 𝟓 , 𝟓 − 𝟓𝒂 = 𝟎 ⇒ 𝒂 = 𝟏
4 + y = 0 ⇒ 𝒚 = −𝟒 , 𝟑𝒙 − 𝟗 = 𝟎 ⇒ 𝒙 = 𝟑
𝟏
𝟐
65 /1/3 14 P.T.O.
∴ (a + x) – (b + y) = ( 1 + 3) – (5 - 4) = 3
65 /1/3 15 P.T.O.
34(a).
2−3𝑡
= ∫5− (1−𝑡2)−4𝑡 𝑑𝑡
2−3𝑡
𝟏
= ∫ (𝑡−2)2 𝑑𝑡
𝑑𝑡 = −3 ∫ 𝑑𝑡 − 4 ∫ dt 𝟏
2−3𝑡 1 1
∫
(𝑡−2)2 𝑡−2 (𝑡−2)2
= −3 log|𝑡 − 2| − 4 ( ) + 𝐶
−1 𝟐
𝑡−2
𝟏
= −3 log|cos 𝑥 − 2| +
4
+𝐶
cos 𝑥−2 𝟐
OR
34(b).
𝑑𝑥
𝑥 +|𝑥|+1
∫−2 𝑥2+4|𝑥|+4
Ans 2
I=
65 /1/3 16 P.T.O.
𝟏
3
𝑥2+4|𝑥|+4 𝑑𝑥 𝑥2+4|𝑥|+4 𝑑𝑥
|𝑥|+1
∫−2 ∫
2 𝑥 2
= + −2
= 𝐼1 + 𝐼2 (𝑠𝑎𝑦)-----(1)
𝐼1 = 0 (∵ 𝑖𝑠 𝑎𝑛 𝑜𝑑𝑑 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛)
𝑥3
𝟏
𝑥2+4|𝑥|+4
2 𝑥+1 |𝑥|+1
𝐼2 = 2 ∫0 𝑑𝑥 (∵ 𝑖𝑠 𝑎𝑛 𝑒𝑣𝑒𝑛 𝑓𝑢𝑛𝑐𝑡𝑖𝑜𝑛. ) 𝟏
𝑥2+4𝑥+4 𝑥2+4|𝑥|+4
2
𝑑𝑥
𝑥+1
=2∫
0 (𝑥+2)2
Put x + 2 = t , so that dx = dt
4 𝑡−1 𝟏
=2∫ 𝑑𝑡 𝟐
2 𝑡2
4
= 2 [∫ (1 − 1 ) 𝑑𝑡]
2 𝑡 𝑡2
= 2 [log|𝑡| + ] 𝟏
14
𝑡 2
= 2 [log 4 + − log 2 ]−
1 1
4 2
𝟏
= 2 log 2 −
1
2 𝟐
35.
Sol.
𝐶𝑜𝑟𝑟𝑒𝑐𝑡
𝑔𝑟𝑎𝑝ℎ
−1
𝟐
Area = 4 ∫ 𝒚 𝒅𝒙
𝟏
𝟎
𝟐
= 4 [ ∫ √𝟒𝟐 − 𝒙𝟐 𝒅𝒙]
𝟏
𝟐 𝟎
𝟐 𝒙
= 2 [ √𝟒𝟐 − 𝒙𝟐 + 𝟖 𝐬𝐢𝐧−𝟏( )] 𝟐
𝒙
𝟐 𝟒 𝟎
= 2 [√𝟏𝟐 + ] = 𝟒 √𝟑 +
𝟖𝝅 𝟖𝝅
𝟔 𝟑
𝟏
65 /1/3 16 P.T.O.
SECTION-E
(Question nos. 36 to 38 are source based/case based/passage based/integrated units of assessment questions
carrying 4 marks each)
36.
−𝟐
−𝝅 𝝅
= 𝟔
−𝟒𝝅 −𝟐𝝅
= 𝟔 or 𝟑 𝟏
65 /1/3 17 P.T.O.
65 /1/3 18 P.T.O.
𝐶𝑜𝑟𝑟𝑒𝑐
𝑡
𝑔𝑟𝑎𝑝ℎ
(iii) (a)
-𝟐
-1≤ 𝟏 − 𝐱 ≤ 𝟏
⇒ −𝟐 ≤ −𝐱 ≤ 𝟎 𝟏
⇒𝟎 ≤ 𝐱 ≤𝟐 𝟐
Domain = [𝟎, 𝟐] 𝟏
𝟐
≤ 𝐬𝐢𝐧−𝟏(𝟏 − 𝐱) ≤
−𝛑 𝛑
𝟐 𝟐
-𝛑 ≤ 𝟐 𝐬𝐢𝐧 (𝟏 − 𝐱) ≤ 𝛑
−𝟏
𝟏
𝟐
So range = [ −𝝅 , 𝝅]
𝟏
𝟐
65 /1/3 18 P.T.O.
65 /1/3 19 P.T.O.
37.
(ii) 𝒅𝜽 =
−𝟓
𝟏
𝒅𝒙 𝟓𝟐+ 𝒙𝟐
(𝒂) = × = × 𝟐𝟎]
𝒅𝜽 𝒅𝜽 𝒅𝒙 −𝟓
𝟏
𝟏
(iii)
𝒅𝒕 𝒅𝒙 𝒅𝒕 𝟓𝟐+ 𝒙𝟐 𝒙=𝟓𝟎 𝟐
= 𝒓𝒂𝒅/𝒔
−𝟏𝟎𝟎 −𝟒
𝟐𝟓𝟐𝟓 𝟏𝟎𝟏 𝟏
or
𝟐
OR
65 /1/3 20 P.T.O.
⇒ = × ⇒ = −𝟏𝟓 𝒎/𝒔
𝟑 −𝟓 𝒅𝒙 𝒅𝒙 𝟏
𝟏𝟎𝟏 𝟐𝟓𝟐𝟓 𝒅𝒕 𝒅𝒕 𝟐
Sol. (i) Let A denote the event of airplane reaching its destination late
𝑬𝟏 = severe turbulence 𝟏
𝟐
𝑬𝟐 = moderate turbulence
}
𝑬𝟑 = light turbulence
P(A) = P (𝑬𝟏) 𝑷( 𝑨|𝑬𝟏) + 𝑷(𝑬𝟐)𝑷(𝑨|𝑬𝟐) + 𝑷(𝑬𝟑)𝑷(𝑨|𝑬𝟑)
𝟏
=𝟑 × 𝟏𝟎𝟎 +𝟑 ×𝟏𝟎𝟎 + ×
𝟏 𝟓𝟓 𝟏 𝟑𝟕 𝟏 𝟏𝟕
𝟑 𝟏𝟎𝟎
𝟏
=𝟑 (𝟏𝟎𝟎 ) =𝟑𝟎𝟎
𝟏 𝟏𝟎𝟗 𝟏𝟎𝟗
𝟐
(ii) P (𝑬 |𝑨) =
𝑷(𝑬𝟐)𝑷(𝑨|𝑬𝟐)
𝟐 𝑷(𝑨)
𝟏 𝟑𝟕
× 𝟏𝟎𝟎 𝟏
𝟑
𝟏𝟎𝟗 𝟏
𝟐
=
𝟑𝟎𝟎
𝟑𝟕 𝟏
𝟏𝟎𝟗 𝟐
=
65 /1/3 20 P.T.O.