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JEE Mains 2021 Solved Question Paper- 24 Feb M1

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Posted by Mahak Jain, 17/3/2021
JEE Mains 2021 Solved Question Paper- 24 Feb M1

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Attempting question papers is best way to practice. In this blog you have JEE Mains 2021 Solved question paper for 24th February shift 1.

In this blog we provide you JEE Mains 2021 solved question paper for free. Here at Kunduz we aim to provide quality solutions from best tutors at Kunduz. These solutions for JEE Mains 2021 question paper are prepared by Kunduz tutors.

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JEE Mains 2021 Solved Question Paper- 24 February Shift 1

Mathematics

Question 1

The area bounded by region inside the circle x2+y2=36 and outside the parabola y2=9x is

  1. 12π+3√3
  2. 36π+3√3
  3. 24π+3√3
  4. 24π-3√3

Correct answer: 3

The area bounded by region inside the circle x2+y2=36 and outside the parabola y2=9x is

Question 2

The locus of mid – point of the line segment joining focus of parabola y2=4ax to a point moving on it, is a parabola equation of whose directrix is

  1. y=0
  2. x=0
  3. x=a
  4. y=a

Correct answer: 2

The locus of mid – point of the line segment joining focus of parabola y2=4ax to a point moving on it, is a parabola equation of whose directrix is JEE Mains 2021 solved question paper

Question 3

The equation of plane perpendicular to plans 3x+y-2z+1=0 and 2x-5y-z+3=0 such that it passes through point (1, 2, -3)

  1. 11x+y+17z+38=0
  2. 11x-y-17z+40=0
  3. 11x+y-17z+36=0
  4. x+11y+17z+3=0

Correct answer: 1

The equation of plane perpendicular to plans 3x+y-2z+1=0 and 2x-5y-z+3=0 such that it passes through point (1, 2, -3)

Question 4

There are 6 Indians 8 foreigners. Find number of committee form with atleast 2 Indians such numbers of foreigners is twice the number of Indians.

  1. 1625
  2. 1050
  3. 1400
  4. 575

Correct answer: 1

There are 6 Indians 8 foreigners. Find number of committee form with atleast 2 Indians such numbers of foreigners is twice the number of Indians JEE Mains 2021 solved question paper

Question 5

If f:R→R is a function defined by f(x)=[x-1]cos((2x-1)π/2) where [x] denotes the greatest integer function, then f is

  1. continuous for every real x.
  2. discontinuous only at x = 1.
  3. discontinuous only at non-zero integral values of x
  4. continuous only at x = 1.

Correct answer: 1

If f:R→R is a function defined by f(x)=[x-1]cos((2x-1)π/2) where [x] denotes the greatest integer function, then f is

Question 6

There are two positive number p and q such that p+q=2 and p4+q4=272. Find the quadratic equation whose roots are p and q

1. x2-2x+2=0

2. x2-2x+135=0

3. x2-2x+16=0

4. x2-2x+130=0

Correct answer: 3

There are two positive number p and q such that p+q=2 and p4+q4=272. Find the quadratic equation whose roots are p and q JEE Mains 2021 solved question paper

Question 7

A point is moving on the line such that the AM of reciprocal of intercepts on axis is 1/4. There are 3 stones whose position are (2, 2) (4, 4) and (1, 1). Find the stone which satisfies the line

  1. (2,4)
  2. (4,4)
  3. (1,1)
  4. None of these

Correct answer: 1

A point is moving on the line such that the AM of reciprocal of intercepts on axis is 1/4. There are 3 stones whose position are (2, 2) (4, 4) and (1, 1). Find the stone which satisfies the line

Question 8

A fair die is thrown n times. The probability of getting an odd number twice is equal to that getting an even number thrice. The probability of getting an odd number, odd number of times is

  1. 1/3
  2. 1/6
  3. 1/2
  4. 1/8

Correct answer: 3

A fair die is thrown n times. The probability of getting an odd number twice is equal to that getting an even number thrice. The probability of getting an odd number, odd number of times is JEE Mains 2021 solved question paper

Question 9

If

JEE Mains 2021 solved question paper

is the root of equation t2-9t+8 then value of 2sinθ/(sinθ + √3sinθ) when 0<θ<π/2, is

  1. 1/2
  2. 1
  3. 2
  4. 4

Correct answer: 1

is the root of equation t2-9t+8 then value of 2sinθ/(sinθ + √3sinθ) when 0<θ<π/2, is

Question 10

Population of a town at time t is given by the differential equation dP/dt=0.5P(t)-450. Also P(0)=850, find the time when population of town becomes zero

  1. ln9
  2. 3ln4
  3. 2ln18
  4. ln18

Correct answer: 3

Population of a town at time t is given by the differential equation dP/dt=0.5P(t)-450. Also P(0)=850, find the time when population of town becomes zero JEE Mains 2021 solved question paper

Question 11

JEE Mains 2021 solved question paper

then ordered pair (a,b) is

  1. (1,3)
  2. (3,1)
  3. (1,1)
  4. (-1,3)

Correct answer: 1

then ordered pair (a,b) is

Question 12

Which of following is tautology ?

  1. A∧(A→B)→B
  2. B→(A∧A→B)
  3. A∧(A∨B)
  4. (A∨B)∧A

Correct answer: 1

Which of following is tautology JEE Mains 2021 solved question paper

Question 13

Let f:R→R, f(x)=2x-1, g(x)=(x-0.5)/(x-1), then f(g(x)) is?

  1. one-one, onto
  2. many-one, onto
  3. one-one, into
  4. many-one, into

Correct answer: 3

Let f:R→R, f(x)=2x-1, g(x)=(x-0.5)/(x-1), then f(g(x)) is

Question 14

The value of (15C1 + 2. 15C2 – 3. 15C3 +…..- 15. 15C15) + (14C1 + 14C3 +……+ 14C11) is

1. 216-14

2. 213-14

3. 213-13

4. 214

Correct answer: 2

The value of (15C1 + 2. 15C2 - 3. 15C3 +.....- 15. 15C15) + (14C1 + 14C3 +......+ 14C11) is JEE Mains 2021 solved question paper

Question 15

The distance of the point P(1, 1, 9) from the point of intersection of plane x+y+z=17 and line (x-3)=(y-4)/2=(z-5)/2

  1. √38
  2. √39
  3. 6
  4. 7

Correct answer: 1

The distance of the point P(1, 1, 9) from the point of intersection of plane x+y+z=17 and line (x-3)=(y-4)/2=(z-5)/2

Question 16

Two towers are 150 m distance apart. Height of one tower is thrice the other tower. The angle of elevation of top of tower from midpoint of their feet are complement to each other height of smaller tower is

  1. 25√3 m
  2. 25/√3 m
  3. 75√3 m
  4. 25 m

Correct answer: 1

Two towers are 150 m distance apart. Height of one tower is thrice the other tower. The angle of elevation of top of tower from midpoint of their feet are complement to each other height of smaller tower is JEE Mains 2021 solved question paper

Question 17

Find the value of

JEE Mains 2021 solved question paper
  1. 1/15
  2. 2/3
  3. 3
  4. 2

Correct answer: 2

Find the value of

Question 18

Tangent at point P(t,t3), of curve y=x3 meets the curve again at Q then ordinate of point which divides PQ in 1:2 internally, is

  1. 0
  2. 2t3
  3. -2t3
  4. 8t

Correct answer: 3

Tangent at point P(t,t3), of curve y=x3 meets the curve again at Q then ordinate of point which divides PQ in 1:2 internally, is JEE Mains 2021 solved question paper

Question 19

The values of k and m such that system of equations 3x+2y-kz=10, x-2y+3z=3, x+2y-3z=5m are inconsistent.

  1. k=3 and m≠7/3
  2. k=3 and m≠7/10
  3. k≠3 and m=7/10
  4. k=2 and m≠7/10

Correct answer: 1

The values of k and m such that system of equations 3x+2y-kz=10, x-2y+3z=3, x+2y-3z=5m are inconsistent

Question 20

Let f(x)=(4x3-3x2)/6 – 2sinx + (2x-1)cosx, then f(x)

  1. decreases in [0.5, ∞)
  2. increase in [0.5, ∞)
  3. decreases in (-∞, ∞)
  4. increase in (-∞, 0.5]

Correct answer: 2

Let f(x)=(4x3-3x2)/6 - 2sinx + (2x-1)cosx, then f(x) JEE Mains 2021 solved question paper

Question 21

The least value of α such that (4/sinx)+(1/(1-sinx))=α has at least one solution in x∈(0,π/2)

Correct answer: 9.00

The least value of α such that (4/sinx)+(1/(1-sinx))=α has at least one solution in x∈(0,π/2)

Question 22

One of the diameter of circle C1😡2+y2-2x-6y+6=0 is chord of circle C2 with centre (2, 1) then radius of C2 is

Correct answer: 3.00

One of the diameter of circle C1:x2+y2-2x-6y+6=0 is chord of circle C2 with centre (2, 1) then radius of C2 is JEE Mains 2021 solved question paper

Question 23

JEE Mains 2021 solved question paper

Correct answer: 1.00

Question 24

where α ∈ R . Suppose Q=qij is a matrix such that PQ=kI, where k∈R, k≠0 and I is the identity matrix of order 3. If q23=-k/8 and det(Q)=k2/2, then value of k22 is equal to

Correct answer: 17.00

where α ∈ R . Suppose Q=qij is a matrix such that PQ=kI, where k∈R, k≠0 and I is the identity matrix of order 3. If q23=-k/8 and det(Q)=k2/2, then value of k2+α2 is equal to JEE Mains 2021 solved question paper

Question 25

Of the three independent events B1, B2 and B3 , the probability that only B2 occurs is β and only B3 occurs is γ. Let the probability p that none of events B1, B2 or B3 occurs satisfy the equations (α-2β)p=αβ and (β-3γ)p=2βγ. All the given probabilities are assumed to lie in the interval (0, 1).

Then (Probability of occurrence of B1)/(Probability of occurrence of B2)=

Correct answer: 6.00

Of the three independent events B1, B2 and B3 , the probability that only B2 occurs is β and only B3 occurs is γ. Let the probability p that none of events B1, B2 or B3 occurs satisfy the equations (α-2β)p=αβ and (β-3γ)p=2βγ. All the given probabilities are assumed to lie in the interval (0, 1)

Question 26

How many 3 × 3 matrices M with entries from {0, 1, 2} are there, for which the sum of the diagonal entries of MTM is 7?

Correct answer: 540.00

How many 3 × 3 matrices M with entries from {0, 1, 2} are there, for which the sum of the diagonal entries of MTM is 7 JEE Mains 2021 solved question paper

Question 27

c is coplanar with a=-i+j+k and b=2i+k, a.c=7 and c is perpendicular to b, then the value of 2|a+b+c| is

Correct answer:75.00

c→ is coplanar with a→=-i+j+k and b→=2i+k, a→.c→=7 and c→ is perpendicular to b→, then the value of 2|a→+b→+c→| is

Question 28

z+α|z-1|+2i=0; z∈C and α∈R, then the value of 2[(αmax)2+(αmin)2] is

Correct answer: 10.00

z+α|z-1|+2i=0; z∈C and α∈R, then the value of 2[(αmax)2+(αmin)2] is JEE Mains 2021 solved question paper

Question 29

Let A={x:x is 3 digit number}, B={x:x=9k+2, k∈I} and C={x:x=9k+l, k∈I, l∈I, 0<l<9}. If sum of elements in A∩B∩C is 274 × 400 then l is

Correct answer: 5.00

Let A={x:x is 3 digit number}, B={x:x=9k+2, k∈I} and C={x:x=9k+l, k∈I, l∈I, 0<l<9}. If sum of elements in A∩B∩C is 274 × 400 then l is

Question 30

-aa |x|+|x-2| = 22, a>2 then the value of -aa x+[x] is, (where [.] represents greatest integer function)

Correct answer: -3.00

-a∫a |x|+|x-2| = 22, a>2 then the value of -a∫a x+[x] is, (where [.] represents greatest integer function) JEE Mains 2021 solved question paper

JEE Main Frequently Asked Questions (FAQs)

Question 1: When is JEE Mains 2021 exams?

Answer: National Testing Agency has announced dates for all phases of JEE Mains. First phase is in February 2021 (23, 24, 25 and 26). Second phase is in March 2021 (15, 16, 17 & 18) , third in April 2021 (27, 28, 29 & 30) and fourth in May 2021 (24, 25, 26, 27 & 28). To get more details about JEE Mains click here.

Question 2: Can I challenge JEE Mains 2021 answer key? How?

Answer: Yes, candidates who have objection to the answer key given by National Testing Agency can go to jeemain.nta.nic.in , from where they can challenge answer key.

Question 3: Does National Testing Agency refund JEE Mains 2021 answer key fees.

Answer: Yes, National Testing Agency refund fees if objection is found valid with proper supporting documents.

Question 4: Who will conduct JEE Mains 2021 Counseling?

Answer: Joint Seat Allocation Authority (JoSAA) is responsible for counseling of JEE Mains 2021 qualified students.


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