22-06-2025
9610ZJM800000030002 JM
PART 1 : PHYSICS
SECTION-I
1)
A particle is moving along x-axis, its “v2–t” graph is shown below. The acceleration at t = 1sec is :
(A) m/s2
(B)
m/s2
(C)
m/s2
(D) 2 m/s2
2) Particle is projected with a velocity of . If it has a constant acceleration of
, then select the correct statement :-
(A) Initially speed of particle increases.
(B) Initially speed of particle decreases.
(C) Speed remain constant throughout the motion but its direction changes.
(D) Speed and direction both remain constant.
3) A projectile is given an initial velocity of , where is along the ground & is along the
2
vertical. If g = 10 m/s , the equation of its trajectory is :-
(A) y = 2x – 5x2
(B) 2y = 3x – 5x2
(C) 4y = 6x – 5x2
(D) 4y = 3x – 5x2
4) If a particle moves in a straight line according to the law x= t3 – 6t2 – 15t, the time interval during
which velocity is negative and acceleration is positive, is
(A) t < 2 and t > 5
(B) 2 < t < 5
(C) –1 < t < 5
(D) –1 < t < 2
5) The position vector of a particle is given as
where a = 1 m/s, b = 1 m, c = m/s2, and d = 1m. The average velocity
during the interval t = 2s to t = 4s is :
(A) 2.5 m/s
(B) 5 m/s
(C) 0.75 m/s
(D) 1.25 m/s
6) If a particle is thrown vertically upward from point A which is 'h' distance from ground. Sign of
displacement, velocity, acceleration at 'C' is (take upward direction as negative) :-
(A) x < 0, v < 0, a < 0
(B) x > 0, v < 0, a < 0
(C) x > 0, v > 0, a > 0
(D) x > 0, v < 0, a > 0
7) Figure shows the velocity (v) of particle plotted again time 't'. For time interval t : [0, 2T], choose
INCORRECT option :
(A) Particle changes its direction of motion at some point
(B) Acceleration of particle remains constant
(C) Displacement is zero
(D) None
8) An aeroplane flies along a straight path A to B and returns back again. The distance between A
& B is λ and the aeroplane maintains the constant speed v with respect to air.There is a steady
wind with a speed u along line AB. The total time taken by the aeroplane in the trip is :-
(A)
(B)
(C)
(D)
9) In the picture shown, a ball starting from rest rolls down a ramp AB, goes along at the horizontal
bottom BC, and then moves up on a smaller ramp CD, thereafter rolls on horizontal plane DE. Ignore
friction and air resistance . Which of the following figure shows variation in speed with time ?
(A)
(B)
(C)
(D)
10) If initial speed of particle is 2m/s. The speed of the particle at x = 6m will be :
(A) m/s
(B) m/s
(C) m/s
(D) 20 m/s
11) A 120 V toaster has a resistance of 12Ω. What must be the minimum rating of the fuse in the
electric circuit to which the toaster is connected ?
(A) 5 A
(B) 10 A
(C) 15 A
(D) 20 A
12) In the circuit shown below, find the decrease in power dissipated in 2Ω resistance after switch is
closed. The battery is ideal :-
(A) 8.34 W
21.21 W
(B)
(C) 3.68 W
(D) 14.72 W
13) Which of the following cannot increase the resistance of a conductor.
(A) Increasing the temperature.
(B) Hammering the conductor
(C) Adding impurity to the conductor
(D) by increasing the mean collision time
14) Rate of dissipation of joule heat in resistance per unit volume is (E is electric field, ρ resistivity):-
(A)
(B)
(C) E2ρ2
(D) None of these
15) A cylindrical resistance is connected across battery ε. Cylinder has uniform free electron density,
mid part of cylinder has larger radius as shown in figure. Then Vd (drift velocity) V/S (distance across
the length of the resistance).
(A)
(B)
(C)
(D)
16) Find the potential at point E if D is grounded, as shown in figure.
(A) 12 volt
(B) –8 volt
(C) 14 volt
(D) –20 volt
17) In a practical wheat stone bridge circuit as shown, when one more resistance of 100Ω is
connected in parallel with unknown resistance 'x', then ratio becomes ' 2 '. ℓ1 is balance length.
AB is a uniform wire. Then value of ' x ' must be :
(A) 50 Ω
(B) 100 Ω
(C) 200 Ω
(D) 400 Ω
18) Three capacitors are connected as shown in the figure, where C1 = 3µF, C2 = 6µF, C3 = 2µF and
E = 10 V. Then the
(a) Energy drawn from the source is 4 × 10–4 J
(b) Energy drawn from the source is 2 × 10–4 J
(c) Heat generated in the system during charging is 2 × 10–4 J
(d) Charges on the three capacitors are equal
Select most appropriate combination :-
(A) 1 & 3
(B) 2 & 3
(C) 1, 3 & 4
(D) 1 only
19)
Find Req between points B and C
(A) R
(B) 5/8R
(C) R/2
(D) 2R
20) A slab of copper of thickness b is inserted in between the plates of parallel plate capacitor as
shown in figure. The separation between the plates is d if , then what is the ratio of
capacitance after insertion of slab to before insertion of slab.
(A)
(B) 2 : 1
(C) 1 : 1
(D) 1 :
SECTION-II
1) Find heat produced in the circuit shown in figure on closing the switch S.
2) Two parallel plate of area A are separated by two different dielectrics as shown in figure. The net
capacitance is , then the value of β is
3) Four identical rectangular plates with length ℓ = 2 cm and breadth b = 3/2 cm are arranged as
shown in figure. The equivalent capacitance between A and C is . The value of x is ___. (Round off
to the Nearest Integer)
4) Ten identical capacitors are connected as shown. The capacitance of each capacitor is 30 μF. The
equivalent capacitance between A and B is x µF then find .
5) If charge on 3μF capacitor is 3μC. Find the charge on capacitor of capacitance C in μC.
PART 2 : CHEMISTRY
SECTION-I
1) An ideal solution is formed by mixing two volatile liquids A and B. XA and XB are the mole fractions
of A and B respectively in the solution and YA and YB are the mole fractions of A and B respectively in
the vapour phase. A plot of along y-axis against along x-axis gives a straight line. What is the
slope of the straight line?
(A)
(B)
(C)
(D)
2) An ideal solution was found to have a vapour pressure of 80 torr when the mole fraction of a non-
volatile solute was 0.2. What would be the vapour pressure of the pure solvent at the same
temperature?
(A) 64 torr
(B) 80 torr
(C) 100 torr
(D) 400 torr
3) Which one of the following statements is false ?
The correct order of osmotic pressure for 0.01 M aqueous solution of each compound is BaCl2 >
(A)
KCl > CH3COOH > sucrose
(B) Isotonic solutions are those solutions which have the same osmotic pressure
Raoult's law states that the vapour pressure of a component over a solution is proportional to its
(C)
mole fraction in liquid state
Two sucrose solutions of same molality prepared in different solvents will have the same
(D)
freezing point depression
4) The boiling point of an aqueous solution of a non volatile solute is 100.15 °C. What is the freezing
point of an aqueous solution obtained by diluting the above solution with an equal volume of water ?
The values of Kb and Kf for water are 0.5 and 1.8 K molality–1 :
(A) –0.54 °C
(B) –0.512 °C
(C) –0.27 °C
(D) –1.86 °C
5) What is the freezing point depression constant of a solvent, 50 g of which contain 1 g non-volatile
solute (molar mass 256 g mol–1) and the decrease in freezing point is 0.40 K ?
(A) 5.12 K kg mol–1
(B) 4.43 K kg mol–1
(C) 1.86 K kg mol–1
(D) 3.72 K kg mol–1
6) The vapour pressure of ethanol and methanol are 42.0 mm and 88.5 mm Hg respectively. An ideal
solution is formed at the same temperature by mixing 46.0 g of ethanol with 16.0 g of methanol. The
mole fraction of methanol in the vapour is :
(A) 0.467
(B) 0.502
(C) 0.513
(D) 0.556
7) What would be the maximum number of emission lines for atomic hydrogen that you would expect
to see with naked eye if the only electronic energy levels involved are those as shown in figure :-
(A) 15
(B) 10
(C) 6
(D) 4
8) What is the ratio of the De-Broglie wave lengths for electrons accelerated through 200 volts
and 50 volts :-
(A) 1 : 2
(B) 2 : 1
(C) 3 : 10
(D) 10 : 3
9) (i) 26Fe54 , 26Fe56, 26Fe57, 26Fe58 (a) Isotopes
(ii) 1H3, 2He3 (b) Isotones
76 77
(iii) 32Ge , 33As (c) Isodiaphers
235 231
(iv) 92U , 90Th (d) Isobars
(v) 1H1, 1D2, 1T3
Match the above correct terms:-
(A) [(i), - a], [(ii) - d], [(iii) - b], [(iv) - c], [(v) - a]
(B) [(i) - a] [(ii) - d], [(iii) - d] [(iv) - c] [v - a]
(C) [v -a] [(iv) - c]. [(iii) - d] [(ii) - b] [(i) - a]
(D) None of them
10) For H atom, the energy required for the removal of electron from various sub-shells is given as
under:- The order of the energies would be :-
(A) E1 > E2 > E3
(B) E3 > E2 > E1
(C) E1 = E2 = E3
(D) None of these
11) Choose the correct statements of the following
(a) Copper can displace iron from FeSO4 solution
(b) Iron can displace copper from CuSO4 solution
(c) Silver can displace copper from CuSO4 solution
(d) Iron can displace silver from AgNO3 solution
(A) a and b
(B) b and c
(C) b and d
(D) a and d
12)
The e.m.f. of following cell at 300K, when
[Cl–] = [Br2] = [Br–] = 0.01M and Cl2(g) at 1 atm.
Cl2(g) + 2Br–(aq.) —→ 2Cl–(aq) + Br2(aq.) E° = 0.29V
(A) +0.29V
(B) 0.23V
(C) –0.35V
(D) 0.35V
13)
Calculate the equilibrium constant for
Hg22+ —→ Hg + Hg2+
Given :
(log2 = 0.3, log3 = 0.4) (100.7 5)
(A) 5 × 10–3
(B) 6 × 10–3
(C) 7 × 10–3
(D) None of these
14) A conductance cell was filled with a 0.02 M KCl solution which has a specific conductance of
2.768 × 10–3 ohm–1 cm–1. If its resistance is 82.4 ohm at 25°C, the cell constant is :-
(A) 0.382 cm–1
(B) 0.2281 cm–1
(C) 0.581 cm–1
(D) 0.928 cm–1
15) A cell is constituted as follows
Pt|H2 (1 atm) |HA1| |HA2| H2 (1 atm) | Pt
The pH of two acids solutions HA1 and HA2 are 5 and 3 respectively. The emf of the cell is -
(A) 0.059 V
(B) 0.0295 V
(C) 0.118 V
(D) – 0.118 V
16) Which of the following statements is incorrect ?
(A) The second ionization energy of sulphur is greater than that of chlorine
(B) The third ionization energy of phosphorus is greater than that of magnesium
(C) The first ionization energy of aluminium is less than as that of gallium
(D) The second ionization energy for boron is greater than that of carbon
17) Select correct statement :-
(A) La and Ac belong to f-block
(B) An element having atomic No.31 belongs to 3rd period.
(C) General outermost shell e– configuration of d-block element is ns1-2(n-1)d1-10
(D) All actinoids are man-made elemetns.
18) Of the following, which one is correct statement ?
(A) Ionic radius of a metal is same as its atomic radius
(B) The ionic radius of a metal is greater than its atomic radius
(C) The atomic radius of a non-metal is more than its ionic radius
(D) The ionic radius of a metal is less than its atomic radius.
19) Which is mismatched regarding the position of the element as given below ?
(A) (Z = 89) – f block, 6th period
(B) (Z = 100) – f block, 7th period
(C) (Z = 115) – d block, 7th period
(D) Both (1) and (3)
20) The correct order of acidic strength is :
(A) Cl2O7 > SO3 > P4O10
(B) CO2 > N2O5 > SO3
(C) Na2O > MgO > Al2O3
(D) K2O > CaO > MgO
SECTION-II
1) Choose the number of correct statements(s) from the following:
(a) Ist ionisation potential of ‘B’ is higher than that of ‘Be’
(b) Electron affinity of ‘O’ is higher than that of ‘Be’
(c) [Ar] 4s23d3 is the electronic configuration of Mn2+
(d) IInd ionisation potential of Na > Ist ionisation potential of Na.
(e) Ist ionisation potential of N > IInd ionisation potential of N.
(f) Electronegativity of Cl > Eelectronegativity of F.
(g) C → C2+ change is called IInd ionisation potential of carbon.
(h) Energy is required to convert He → He+
(i) Conversion of O → O2– is exothermic.
2) Number of pairs for which size of 1st element is bigger than 2nd.
[Li+, Mg2+] [Ne, Ar] [Be, B] [O2–, F–]
[Cl–, Cl] [F–, H–] [Na+, Mg+2]
3) The magnitude of potential energy of electron in nth excited state of He+ ion is times the kinetic
energy of electron in the first excited state of Li2+ ion. Find "n"
4) What is the sum of van’t Hoff factor for Ca(NO3)2 and K4[Fe(CN)6] if they are 60% and 70%
dissociated respectively?
5) Calculate Ecell for following
[Given ]
Fill your answer by multiplying it with 100.
PART 3 : MATHEMATICS
SECTION-I
1) If sin–1(1 – x) – 3sin–1x = cos–1x, then the value of x is
(A) 1
(B)
(C) 0
(D)
2) Sum of all the real values of x satisfying the equation is
(A)
(B) 5
(C)
(D) 7
3) If , where , then number of possible values of x + y is
(A) 0
(B) 1
(C) 2
(D) 3
4)
(A) Unique solution
(B) Two solutions
(C) No solution
(D) More than two solution
5) If sin–1 < π – 3, then
(A) x ∈ (–1, 0)
(B) x ∈ (0, 1)
(C) x ∈ (–1, 1)
(D) x ∈ ϕ
6) Let f(x) = x2 – 2ax + a – 2 and g(x) = . If the complete set of real values of 'a'
for which ∀ x ∈ R is (k1, k2), then the value of (10k1 + 3k2) is equal to
[Note : [k] denotes greatest integer less than or equal to k.]
(A) 35
(B) 27
(C) 20
(D) 8
7) The value of tan–1 + tan–1 + tan–1 , where a,b,c ∈ R+ and λ = a + b + c, is equal to
(A)
(B) π
(C)
(D) None
8) If are roots of the equation ,
then the value of is
(A)
(B)
(C)
(D)
9) The value of is
(A)
(B)
(C)
(D)
10) Let such that then α equals
(A)
(B)
(C)
(D)
11) If x > 1, y > 1 and logxy + logyx2 = 4 and x > y, then logxy is
(A) 2
(B)
(C)
(D)
12) Let f(x) = min{tan–1x, cot–1x} and . If α, β (where α < β) be the integers in the
range of g(x), then the value of
cos–1(cos α) + sin–1(sin β) is
(A) 3 – π
(B) π
(C) 1
(D) π – 3
13) Which of the following values of ‘x’ will satisfy the inequality
(A)
(B)
(C)
(D)
14) The value of , where x ∈ (0, 90°) is equal to
(A) 0
(B) 1
(C) 2
(D) none of these
15) Number of integers ≤ 8 satisfying the inequality is
(A) 5
(B) 6
(C) 7
(D) 8
16) The number of real solution(s) of is
(A) 0
(B) 1
(C) 3
(D) infinite
17) Complete solution set of the equation is equal to
(A)
(B)
(C) [1, 2]
(D) (-2, 2)
18) It ax + b sec(tan–1 x) = c and ay + b sec(tan–1y) = c, then is equal to
(A)
(B)
(C)
(D)
19) If x & y are positive integers such that log2(xy) = 4 + ƒ1 & log2(x/y) = 2 + ƒ2, where ƒ1, ƒ2 ∈ [0, 1),
then number of integers for x is
(A) 8
(B) 9
(C) 10
(D) 11
20) Let f(x) be even periodic function with period '3' such that . The
number of solutions of the equation in [–3,100] is
(A) 68
(B) 69
(C) 102
(D) 103
SECTION-II
1) If log3a = p, log9b = p3, and , then |α + β + γ + δ|
is
2) If range of the function f(x) = tan–1(3x2 + (k – 1)x + 3) is for x ∈ R, then find the sum of all
possible real value(s) of k ?
3) The number of solutions of the equation 1 + x2 + 2x sin(cos–1y) = 0 is equal to 'k' and ordered
pairs (x,y) which satisfy the equation are (ai,bi) for i = 1,2,3,...k then value of is
4)
What is the value of
5) Sum of Integral values of ‘x’ satisfying
= 1 is
ANSWER KEYS
PART 1 : PHYSICS
SECTION-I
Q. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
A. B B C B D C D A A C B D D B A B B C C B
SECTION-II
Q. 21 22 23 24 25
A. 0 4 2 6 9
PART 2 : CHEMISTRY
SECTION-I
Q. 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45
A. A C D C A C D A A C C D A B C B C D D A
SECTION-II
Q. 46 47 48 49 50
A. 3 5 5 6 3
PART 3 : MATHEMATICS
SECTION-I
Q. 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70
A. C A C C C C B B B D C C D C C A A B A D
SECTION-II
Q. 71 72 73 74 75
A. 2 2 0 0 9
SOLUTIONS
PART 1 : PHYSICS
1)
From the given graph
v2 = 2t
va = 1
v at t = 1 sec is
m/sec2
2)
Since is –ve thats why speed decreases initially.
3)
vx = 2
vy = 3
x = 2t
y = 3t –
y=
4y = 6x – 5x2
4)
⇒ required interval
2<t<5
5)
Since position vector
∴ x = at + b and y = ct2 + d
x = t + 1 and y =
Now average velocity.
Its magnitude is
= 5/4 m/s
6)
Because downward direction is considered positive so by sign convention x > 0, v > 0, a > 0.
7)
Theoretical
8) t = t1 + t2
9) Velocity increases down the incline, then becomes constant in BC as there is no friction,
decreases in CD up the incline and again becomes constant in DE.
10) Area = 8 + 6 + 4 = 18
∴
⇒v= m/s
11)
0
12) i =
P0 = 50 W
iT =
I2 = 7 × = 4.2 A
P = 4.22 × 2 = 35.28 W.ΔP = 14.72 W
13)
Theoretical
14)
= ρJ2 = E2/ρ
15) i = JA
J = neVd
i = AneVd
i = constant
AVd = Constant
16)
⇒ VD = 0
∴ VE = –4 × 2 = –8 volt
17)
∴ wheat stone bridge is in balanced condition
so
∴ = 2 ⇒ x = 100 W
18)
19)
Wheatstone bridge
20) Copper slab is conducting material. Hence the effective width of capacitor in second case
will become (d – t). (here d is width of capacitor and t is thickness of the slab).
, , given ⇒
21)
70 = 7 × Vf
Vf = 10V
Heat
= =0
22)
23)
24)
25) 6μF & 3μF capacitor are in parallel
∴ Voltage across them will be same
Q = CV
3μC = 3μF × V
V = 1V across 3μF
Therefore change on 6μF
Q = 6μF × 1 = 6μC
Total change = 6 + 3 = 9μC
9h series charge are same.
PART 2 : CHEMISTRY
26) ⇒
YA =
y = C + m.x
27) = xsolute
Po – 80 = 0.2 Po
Po = 100 torr
28) For different solvents, Kf will be different.
29) ΔTb = Kb × m
0.15 = 0.5 × m
m = 0.3
∵ due to dilution
m1v1 = m2v2
0.3 × v = m2 × 2V
m2 = 0.15
ΔTf = Kf × m2
= 1.8 × 0.15
= 0.27°C
so F.P. of solution = –0.27°C
30)
31) Ethanol Methanol
(P) (B)
YB = ?
YB =
YB = = 0.513
32) Only 4 lines in visible region (Balmer)
6 → 2, 5 → 2, 4 → 2, 3 → 2
33)
V1 = 200
V2 = 50
If we are concern about e– then mass and charge (e) are same
so ⇒ =1:2
34) Isotopes = Same atomic no.
Isotones = Same no. of neutrons
Isodiaphers = Same (N–P)
Isobars = Same mass no.
35) Energy of single e– species depends upon 'n' only
So energy of 3s = 3p = 3d
36)
A. Question Explanation:
The question asks you to identify which of the given metal displacement reactions are
spontaneous, based on the reactivity series of metals.
B. Concept: Electrochemical series
C. Solution -
A. Reactivity Series of Metals: A list of metals arranged in order of their reactivity. A more
reactive metal can displace a less reactive metal from its salt solution.
B. Displacement Reaction: A reaction in which a more reactive metal displaces a less reactive
metal from its salt solution.
C. Electrochemical Series: The electrochemical series is a more precise list, but for this
question, a general understanding of metal reactivity is sufficient.
D. General reactivity order from most to least reactive. K, Na, Ca, Mg, Al, Zn, Fe, Pb, H, Cu, Ag,
Au.
D. Final Answer:
Let's analyze each statement:
A. (a) Copper can displace iron from FeSO4 solution: Copper is less reactive than iron, so
this is incorrect.
B. (b) Iron can displace copper from CuSO4 solution: Iron is more reactive than copper, so
this is correct.
C. (c) Silver can displace copper from CuSO4 solution: Silver is less reactive than copper, so
this is incorrect.
D. (d) Iron can displace silver from AgNO3 solution: Iron is more reactive than silver, so this
is correct.
Therefore, the correct statements are (b) and (d).
The correct answer is 3. b and d.
E. Question Level - Medium
37)
At 300 K
E = E° –
E = 0.29 –
0.29 + 0.06 ⇒ 0.35 V
38) + 2e– → 2Hg ...(1)
+
2e– → Hg ...(2)
(1) – (2)
→ Hg + Hg+2 E° = 0.78 – 0.85
⇒ – 0.07 V
– 0.07 = 0.03 log K
–2.3 = log K
K = 10–2.3
⇒ 10–3 × 10+0.7 = 5 × 10–3
39) k=
2.768 × 10–3 =
constant = 82.4 × 2.768 × 10–3 = 0.2281
40) Anode :
Cathode :
________________________________
________________________________
= 0.118 volt
41) (i)
(ii)
(iii)
(size almost same due to transition contraction)
Al < Ga (IE)
(iv)
42) General outermost shell e– configuration of d-block is ns1–2 (n–1)d1-10
43) A cation is smaller than it's parent atom.
44) (Z = 89) d-block, 7th period
(Z = 115) p-block, 7th period
45)
Acidic character of non–metallic oxides increases along a period (from left to right) of periodic
table.
Cl2O7 > SO3 > P4O10
46) b,d,h are correct
47)
1, 3, 4 , 5 , 7
48) |P.E.| = 2 × |T.E|
K.E = | –T.E.| = 13.6 ×
2 × 13.6 ×
(n + 1)2 = 36
n+1=6⇒n=5
49)
50) Concentration =0
= 0.03
PART 3 : MATHEMATICS
51) sin–1(1 –x) – 3sin–1x = cos–1x
sin–1 (1 – x) – 3sin–1x = – sin–1x
sin–1 (1 – x) = + 2sin–1x
2sinÝx = –cos–1 (1 – x) ..(1)
Domain is x ∈ [0, 1]
sin–1x = θ, θ ∈
x = sinθ ..(2)
By (1) and (2)
2θ = –cos–1 (1 – sinθ)
cos–1 (1 – sinθ) = –2θ, –2θ ∈ [–π, 0]
Only possible when –2θ = 0.
⇒ θ=0 ⇒ x = 0.
52) ⇒
⇒ (log2x + log2(x – 1))(log2(x – 1) – log2x) + (log2x)2 = 4
⇒ (log2(x – 1))2 – (log2x)2 + (log2x)2 = 4
(log2(x – 1))2 = 4
log2(x – 1) = 2, –2
53)
x = 25 & cosy = 1 x = 25 & y = 0 or y = 2π
54)
log is defined when
Case – I when
no solution
Case – II
55) =2+
∴ 2< ≤4
sin–1 <π–3
⇒ π– <π–3
⇒ 2+
⇒ >1
⇒ 2 > 1 + x2
⇒ x2 < 1
⇒ x ∈ (–1, 1)
56) We have g(x) = =2+
As, sin–1
∴ = – 2, – 1, 0, 1.
Range of g(x) = {0, 1, 2, 3} for <0∀x∈R
⇒ f(0) < 0 and f(3) < 0
Now, f(0) < 0 ⇒ a – 2 < 0 ⇒ a < 2
and f(3) < 0 ⇒ 9– 6a + a – 2 < 0
a>
∴ a∈ .
Hence, k1 = , k2 = 2
∴ (10k1 + 3k2) = 14 + 6 = 20. Ans.
57) =
=
=π
58) We have,
and
59) =
60)
Let
As
tan–1 x + tan–1y = if xy ≤ 1
61) logxy + 2logyx = 4
a2 – 4a + 2 = 0
∵x>y ∴ logxy < 1
a<1
Hence
62)
Range of g(x) is
⇒ α = –2 & β = –1
⇒ cos–1cos(–2) + sin–1(sin(–1)) = 1
63)
From we get
Furthermore,
or . Then we have &
64)
and logsecx(sec2x – tan2x) = logsecx(1) = 0
65)
2(x – 1)5 ≥ x
If x ≤ 0, the RHS is greater than LHS.
So those integers don't satisfy the inequality
if both numbers x and x – 1 are greater than 1 then inequality holds true
but RHS is also a multiple of 2 so
x ≥ 1 and x – 1 ≥ 1
⇒x≥2
66)
67) Hints : Use |a| + |b| = |a + b|
68)
Let tan–1x = α and tan–1y = β then, a tan α + b sec α = c and a tan β + b sec β = c
Obviously a tanθ + b secθ = c has roots tan α and tan β
⇒ (a2 – b2) tan2θ – 2 ac tan θ + c2 – b2 = 0
∴ tanα + tanβ = and tanα tan β =
So
69) log2x + log2y = 4 + ƒ1
log2x – log2y = 2 + ƒ2
—————————
2log2x = 6 + ƒ1 + ƒ2 or x = 23 + ƒ
23 < x < 24
⇒ Number of x = 8
70)
for one period : [–3,0] number of solution is '3'
so for [–3,99], number of solution = 34 × 3
for [99, 100], number of solution = 1
71) log3a = p, log9b = p3 ⇒ log3b = 2p3
= 2 log3a + 4 log3b – 6 log3c
= 2p + 4(2p3) – 6(p2 + 1)
= 8p3 – 6p2 + 2p – 6
α = 8, β = –6, γ = 2, δ = –6
|α + β + γ + δ| = 2
72) Let g(x) = 3x2 + (k – 1)x + 3; x ∈ R
∴ Range of g(x) ∈ [0, ∞)
so, D = 0 ⇒ (k – 1)2 – 4.3.3 = 0
k – 1 = ±6
∴ k = 7, –5
73) sin(cos–1y) =
as
So, sin(cos–1y) = ±1
& x = ±1
If sin cos–1y = –1 ⇒ cos–1y = (not possible)
& if sin cos–1y = 1 ⇒ cos–1y = ⇒y=0
∴ solution is (–1, 0)
∴ k = 1 & (a1, b1) = (–1, 0)
∴ k + a1 + b1 = 0
74) Substituting x by x2 we see that
All the terms of the desired expression cancel out
Required value = 0.
75)
Put log2x = t
⇒ |t–2| + |t – 1| =1