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CBSE Class 12 Maths 2026 Question Paper 65/5/1 with Solutions

All 45 questions from the CBSE Class 12 Mathematics board paper, Set 65/5/1 (2026), with answers and step-by-step solutions. Total 80 marks. Tap “Show answer & solution” under any question.

Set 65/1/1Set 65/1/2Set 65/1/3Set 65/2/1Set 65/2/2Set 65/2/3Set 65/3/1Set 65/3/2Set 65/3/3Set 65/4/1Set 65/4/2Set 65/4/3Set 65/5/1Set 65/5/2Set 65/5/3
Q11 markMCQMatrices

If matrix is such that , then :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (B)
  1. .
  2. gives , i.e. .
Q21 markMCQMatrices

If A is a square matrix such that , then is equal to :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (B)
  1. .
  2. .
  3. So .

For the inverse trigonometric functions, which of the following Principal Value Branch is not correctly defined ?

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (D)
  1. The principal value branch of is , since is not defined at .
  2. Options (A), (B) and (C) are the standard principal value branches, so (D) is not correctly defined.
Also asked in: 2026 65/5/2, 2026 65/5/3
Q41 markMCQMatrices

Let and . If A + B + C = O, then matrix C is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (C)
  1. .
  2. .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q51 markMCQDeterminants

If A is a non-singular matrix, then which of the following is not true ?

  1. (A)adj A is singular
  2. (B)
  3. (C)
  4. (D) exists
Show answer & solution
Answer: (A) adj A is singular
  1. For an matrix, when , so adj A is non-singular.
  2. (B), (C), (D) are all true for a non-singular matrix, so (A) is not true.
Also asked in: 2026 65/5/2, 2026 65/5/3

If
is continuous at , then the value of k is :

  1. (A)Any real value
  2. (B)6
  3. (C)
  4. (D)
Show answer & solution
Answer: (D)
  1. For , .
  2. .
  3. Continuity at needs .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q71 markMCQDeterminants

If the area of with vertices , and is 5 sq. units, then values of k are :

  1. (A)3, 1
  2. (B), 3
  3. (C), 2
  4. (D)0, 2
Show answer & solution
Answer: (B) , 3
  1. Area .
  2. or .
Also asked in: 2026 65/5/2, 2026 65/5/3

Derivative of , with respect to x is :

  1. (A)
  2. (B)1
  3. (C)
  4. (D)
Show answer & solution
Answer: (A)
  1. Let , so .
  2. , and for .
  3. .
Also asked in: 2026 65/5/2, 2026 65/5/3

Absolute minimum value of in the interval is :

  1. (A)
  2. (B)2
  3. (C)5
  4. (D)30
Show answer & solution
Answer: (C) 5
  1. on , so f is decreasing there.
  2. Minimum is at : (maximum ).
Also asked in: 2026 65/5/2, 2026 65/5/3
Q101 markMCQIntegrals

is equal to :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (B)
  1. , so the integrand is (taking ).
  2. .
Q111 markMCQIntegrals

The value of is equal to :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (A)
  1. .

An ant is observed crawling on a sheet of paper along a straight line given by equation . Area of the surface covered by the ant bounded by y-axis, x-axis and is :

  1. (A)1 sq. unit
  2. (B)3 sq. units
  3. (C)2 sq. units
  4. (D)4 sq. units
Show answer & solution
Answer: (B) 3 sq. units
  1. For , , so the region lies below the x-axis.
  2. Area sq. units.
Also asked in: 2026 65/5/2, 2026 65/5/3

The order and degree of the differential equation is :

  1. (A)Order = 3, Degree = 3
  2. (B)Order = 2, Degree = 2
  3. (C)Order = 3, Degree = 1
  4. (D)Order = 2, Degree = 1
Show answer & solution
Answer: (A) Order = 3, Degree = 3
  1. Highest derivative is , so order = 3.
  2. It is a polynomial in derivatives and the highest order derivative appears with power 3, so degree = 3.

The general solution for the differential equation is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (A)
  1. .
  2. Integrating: , i.e. .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q151 markMCQLinear Programming

The corner points of the feasible region determined by the system of linear constraints are (0, 0), (0, 40), (20, 40) (60, 20) and (60, 0). If the objective function of an LPP is , then the maximum value is :

  1. (A)200
  2. (B)300
  3. (C)240
  4. (D)120
Show answer & solution
Answer: (B) 300
  1. Z at the corners: (0, 0): 0; (0, 40): 120; (20, 40): 200; (60, 20): 300; (60, 0): 240.
  2. Maximum value is 300 at (60, 20).
Also asked in: 2026 65/5/2, 2026 65/5/3
Q161 markMCQVector Algebra

If position vector of a point (24, n) is such that , then the value of n is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (D)
  1. .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q171 markMCQVector Algebra

If vectors and , represent the two strips of the Red Cross sign placed outside a doctor’s clinic, then the value of is :

  1. (A)1
  2. (B)
  3. (C)
  4. (D)0
Show answer & solution
Answer: (C)
  1. The two strips of a Red Cross sign are perpendicular, so .
  2. .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q181 markMCQProbability

If and , then is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (D)
  1. , .
  2. .
  3. .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q191 markAssertion–ReasonRelations and Functions

Assertion (A): A relation R on the set {1, 2, 3} defined as R = {(1, 1), (1, 2), (2, 1), (2, 2), (3, 3)} is an equivalence relation.
Reason (R): A relation that is reflexive, symmetric and transitive is an equivalence relation.

  1. (A)Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
  2. (B)Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
  3. (C)Assertion (A) is true, but Reason (R) is false.
  4. (D)Assertion (A) is false, but Reason (R) is true.
Show answer & solution
Answer: (A) Both A and R are true and R is the correct explanation of A.
  1. Reflexive: (1, 1), (2, 2), (3, 3) are in R.
  2. Symmetric: (1, 2) and (2, 1) are both in R.
  3. Transitive: (1, 2), (2, 1) give (1, 1) in R; (2, 1), (1, 2) give (2, 2) in R; all other cases are trivial.
  4. So R is an equivalence relation; R is the definition of an equivalence relation and explains A.
Also asked in: 2026 65/5/2, 2026 65/5/3
Q201 markAssertion–ReasonLinear Programming

Assertion (A): Consider a Linear Programming Problem with minimise subject to constraints , , which gives minimum Z at infinitely many points. The corner points of feasible region are (0, 3) and (6, 0).
Reason (R): If two corner points produce the same minimum value of the objective function, then every point on the line segment joining the points will give the same minimum value.

  1. (A)Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
  2. (B)Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
  3. (C)Assertion (A) is true, but Reason (R) is false.
  4. (D)Assertion (A) is false, but Reason (R) is true.
Show answer & solution
Answer: (A) Both A and R are true and R is the correct explanation of A.
  1. Lines and meet at (0, 3); the feasible (unbounded) region has corner points (0, 3) and (6, 0).
  2. and ; since in the region, the minimum is 6.
  3. Every point on the segment joining (0, 3) and (6, 0) gives , so the minimum occurs at infinitely many points.
  4. R is a true property and is exactly why A holds.
Also asked in: 2026 65/5/2, 2026 65/5/3
Q212 marksVery Short AnswerInverse Trigonometric Functions

Evaluate .

Show answer & solution
Answer:
  1. .
  2. (principal value in ).
  3. .
Q222 marksVery Short AnswerContinuity and Differentiability

Differentiate with respect to .

Show answer & solution
Answer:
  1. Let , .
  2. .
  3. .
  4. .
Also asked in: 2026 65/5/2, 2026 65/5/3
OR
Q22 (OR) (OR)2 marksVery Short AnswerContinuity and Differentiability

If , show that .

Show answer & solution
Answer: Proved.
  1. .
  2. .
  3. Hence .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q232 marksVery Short AnswerApplication of Derivatives

Determine the values of x for which , is an increasing function.

Show answer & solution
Answer: f is increasing for all real , i.e. on and .
  1. .
  2. for every .
  3. So f is increasing on and on .
Q242 marksVery Short AnswerVector Algebra

Three honey bees were found flying along the vectors , and respectively. Find the value of such that the path for is perpendicular to .

Show answer & solution
Answer:
  1. .
  2. Perpendicular to : .
  3. .
Also asked in: 2026 65/5/2, 2026 65/5/3
OR
Q24 (OR) (OR)2 marksVery Short AnswerVector Algebra

If A, B and C be three non-collinear points such that and , then find the area of .

Show answer & solution
Answer: sq. units
  1. .
  2. Its magnitude is .
  3. Area sq. units.
Also asked in: 2026 65/5/2, 2026 65/5/3
Q252 marksVery Short AnswerThree Dimensional Geometry

Find the angle between the following pair of lines :
and

Show answer & solution
Answer:
  1. Write the lines as and .
  2. Direction ratios: (3, 2, 6) and (1, 2, 2).
  3. .
  4. .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q263 marksShort AnswerApplication of Derivatives

A spherical balloon loses its volume due to escape of air from it in such a way that decrease of volume at any instant is proportional to its surface area. Show that the radius is decreasing at a constant rate.

Show answer & solution
Answer: Proved.
  1. , .
  2. Given , where is constant.
  3. , so .
  4. , a constant; so the radius decreases at a constant rate.
Q273 marksShort AnswerIntegrals

Find :

Show answer & solution
Answer:
  1. and .
  2. Integrand .
  3. By parts: .
  4. So .
Also asked in: 2026 65/5/2, 2026 65/5/3
OR
Q27 (OR) (OR)3 marksShort AnswerIntegrals

Evaluate :

Show answer & solution
Answer:
  1. .
  2. .
  3. Value .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q283 marksShort AnswerDifferential Equations

Solve the differential equation .

Show answer & solution
Answer:
  1. Write as , i.e. (linear in x).
  2. I.F. .
  3. .
  4. So .
Q293 marksShort AnswerLinear Programming

Solve the following Linear Programming Problem graphically :
Maximize
subject to constraints


.

Show answer & solution
Answer: Maximum Z = 260 at x = 200, y = 600.
  1. Draw through (500, 0), (0, 1000) and through (800, 0), (0, 800); they meet at (200, 600).
  2. Feasible region (towards the origin, in the first quadrant) has corners (0, 0), (500, 0), (200, 600), (0, 800).
  3. Z values: 0, 200, 260, 240.
  4. Maximum Z = 260 at (200, 600).
Also asked in: 2026 65/5/2, 2026 65/5/3
Q303 marksShort AnswerVector Algebra

Let three toys A, B and C be placed in the same straight line. If the position vectors of A, B and C are , and respectively, find the value of ‘a’.

Show answer & solution
Answer:
  1. , .
  2. Collinear, so : from the parts, .
  3. .
Also asked in: 2026 65/5/2, 2026 65/5/3
OR
Q30 (OR) (OR)3 marksShort AnswerVector Algebra

If , and are unit vectors, then prove that
.

Show answer & solution
Answer: Proved.
  1. LHS .
  2. , so .
  3. Hence LHS .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q313 marksShort AnswerProbability

A die is rolled. Consider events :
A = {1, 2, 5}, B = {3, 5}, C = {2, 3, 4, 5}
and hence find :
(i) and
(ii) and

Show answer & solution
Answer: (i) , (ii) ,
  1. , , so .
  2. ; .
  3. , : .
  4. , : .
Also asked in: 2026 65/5/2, 2026 65/5/3
OR
Q31 (OR) (OR)3 marksShort AnswerProbability

A box contains 6 cards numbered 1 to 6. A student is asked to pick up two cards, one by one after replacement and note down the numbers on the cards. Let A be the event of getting sum of the numbers on two cards as 10, and B, the event of a number other than 4 on the first card selected.
Find P(A and B) and find whether the events A and B are independent events or not.

Show answer & solution
Answer: ; A and B are not independent.
  1. There are 36 equally likely outcomes.
  2. A = {(4, 6), (5, 5), (6, 4)}, so .
  3. (first card is not 4).
  4. , so .
  5. , so A and B are not independent.
Also asked in: 2026 65/5/2, 2026 65/5/3
Q325 marksLong AnswerDeterminants

A man goes to buy fruits from the market. The shopkeeper informs him that 4 apples, 3 oranges and 2 bananas cost ₹ 60; 2 apples, 4 oranges and 6 bananas cost ₹ 90; whereas 6 apples, 2 oranges and 3 bananas cost ₹ 70. Using matrix method, find the cost of one fruit of each kind.

Show answer & solution
Answer: Apple ₹ 5, orange ₹ 8, banana ₹ 8.
  1. Let the costs be x (apple), y (orange), z (banana): , , .
  2. , .
  3. .
  4. .
  5. Apple ₹ 5, orange ₹ 8, banana ₹ 8.

If , show that
.

Show answer & solution
Answer: Proved.
  1. Read the right side as .
  2. Differentiate: .
  3. RHS .
  4. Multiply by : , i.e. .
Also asked in: 2026 65/5/2, 2026 65/5/3
OR
Q33 (OR) (OR)5 marksLong AnswerContinuity and Differentiability

Find the differential of with respect to x.

Show answer & solution
Answer:
  1. Let : , so .
  2. Let : .
  3. Numerator .
  4. .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q345 marksLong AnswerApplication of Integrals

Sketch the curve and find the area of the region enclosed by it, using integration.

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Answer: sq. units
  1. : an ellipse with centre O, x-intercepts , y-intercepts .
  2. In the first quadrant ; by symmetry Area .
  3. .
  4. Area sq. units.
Q355 marksLong AnswerThree Dimensional Geometry

Find the foot of the perpendicular from the point (0, 2, 3) on the line and hence find the length of the perpendicular.

Show answer & solution
Answer: Foot (2, 3, ); length units.
  1. Standard form: .
  2. General point ; with P(0, 2, 3).
  3. : .
  4. Foot Q = (2, 3, ).
  5. units.
Also asked in: 2026 65/5/2, 2026 65/5/3
OR
Q35 (OR) (OR)5 marksLong AnswerThree Dimensional Geometry

Find the value of p if the shortest distance between the lines
and

is units.

Show answer & solution
Answer: or
  1. , magnitude .
  2. .
  3. .
  4. SD .
  5. or .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q364 marksCase StudyRelations and Functions

A school wants the students of class XII to do a project on ‘Sustainability’ keeping the world environment in mind. They select the student participants on the basis of an essay writing competition.
7 students out of 80 are selected for the project and are categorized into two sets such that :
Girl students belong to Set A = ,
Boy students belong to Set B = .
Based on the above information, answer the following questions :
(i) How many relations are possible from Set A Set B ? (1)
(ii) Let R be a relation from A B such that R = . Is R an injective function ? Justify your answer. (1)
(iii) (a) Let the relation R from A A be such that R = {(x, y), x, y A, x and y are students from the same colony in the city} Verify if R is an equivalence relation. (2)
OR (iii) (b) Verify if any function f : B A is bijective. Give reason to support your answer. (2)

Show answer & solution
Answer: (i) (ii) No, R is not a function ( has two images), so it is not an injective function. (iii) (a) Yes, R is an equivalence relation. OR (iii) (b) No; since n(B) = 3 < n(A) = 4, no function from B to A can be onto, so none is bijective.
  1. (i) , so the number of relations is .
  2. (ii) is related to both and , so R is not a function and hence not an injective function.
  3. (iii) (a) Reflexive: every student is from the same colony as himself/herself. Symmetric: if x and y are from the same colony, so are y and x. Transitive: if x, y and y, z are from the same colony, then x, z are too. So R is an equivalence relation.
  4. (iii) (b) B has 3 elements and A has 4, so a function f : B → A has at most 3 images and cannot be onto; hence no such f is bijective.
Also asked in: 2026 65/5/2, 2026 65/5/3
Q374 marksCase StudyProbability

There are three types of vaccines , , , available in the market to protect the population of the country from spread of certain infection. According to a survey conducted, it was found that 25% of the population was given Vaccine , 35% of the population was given Vaccine and 40% of the population was given Vaccine . The survey also stated that the probabilities that Vaccines , and would protect against the infection were 60%, 55% and 50% respectively.
Based on the above information, answer the following questions :
Find the probability that :
(i) The person taking vaccine will get infected. (1)
(ii) If a person is chosen randomly, he/she will be protected from the infection. (1)
(iii) (a) The person was given Vaccine , given that the randomly chosen person is infected. (2)
OR (iii) (b) The person was given Vaccine , given that the randomly chosen person is not infected. (2)

Show answer & solution
Answer: (i) 0.45 (ii) 0.5425 (iii) (a) OR (iii) (b)
  1. , , ; P(protected | ) = 0.60, 0.55, 0.50.
  2. (i) P(infected | ) = 1 − 0.55 = 0.45.
  3. (ii) P(protected) = 0.25(0.60) + 0.35(0.55) + 0.40(0.50) = 0.15 + 0.1925 + 0.2 = 0.5425.
  4. (iii) (a) P(infected) = 1 − 0.5425 = 0.4575; P( | infected) = .
  5. (iii) (b) P( | not infected) = .
Also asked in: 2026 65/5/2, 2026 65/5/3
Q384 marksCase StudyApplication of Derivatives

A company produces cylindrical tumblers, open from the top. Since they want uniformity in the product, they fix the surface area of the tumblers produced.
Based on the above information, answer the following questions :
If for a tumbler, V is its volume, h the height and r the radius of the circular base, then :
(i) Differentiate its volume with respect to radius of the base, where the surface area is constant. (2)
(ii) If the company wants to maximize the volume of each tumbler, then establish a relation between its height and the radius of the base. (2)

Diagram for CBSE 2026 Class 12 Maths question 38
Show answer & solution
Answer: (i) , where S is the fixed surface area (ii) h = r
  1. Let the fixed surface area be , so .
  2. .
  3. (i) .
  4. (ii) .
  5. , so V is maximum when h = r (height equals radius of the base).
Also asked in: 2026 65/5/2, 2026 65/5/3
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