MonoMath CBSE
CBSE Maths › Class 12 PYQs › 2026

CBSE Class 12 Maths 2026 Question Paper 65/4/3 with Solutions

All 45 questions from the CBSE Class 12 Mathematics board paper, Set 65/4/3 (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

The following graph represents :

Diagram for CBSE 2026 Class 12 Maths question 1
  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (A)
  1. The curve exists only for , so the domain is .
  2. It goes from through down to , so the range is and it is decreasing.
  3. This is the principal branch of .
Q21 markMCQMatrices

Let be a matrix whose elements are given by . Then is given by :

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

The greatest integer function, , is not differentiable at how many points ?

  1. (A)At only one point
  2. (B)At only two points
  3. (C)At no point
  4. (D)At three points
Show answer & solution
Answer: (B) At only two points
  1. jumps at every integer, so it is discontinuous (hence not differentiable) at integers.
  2. In the integers are and .
  3. Elsewhere is constant on each piece and differentiable. So it fails at exactly two points.
Also asked in: 2026 65/4/1, 2026 65/4/2

The area of the region bounded by the curve y = x and x-axis, between x = 0 and x = 2 is :

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

If is continuous at x = 0, then the value of k is :

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

A cylindrical tank is being filled with sand at a rate of 314 m/h. If the radius of the tank is 10 m, then the height of sand in the tank increases at the rate of :

  1. (A)1.1 m/h
  2. (B)1 m/h
  3. (C) m/h
  4. (D) m/h
Show answer & solution
Answer: (B) 1 m/h
  1. with fixed, so .
  2. .
  3. Taking , m/h.

The principal value of is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (B)
  1. (principal range ).
  2. (principal range ).
  3. Value .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q81 markMCQDeterminants

If points (2, 3), (0, 4) and (p, 2) are collinear, then the value of p is :

  1. (A)
  2. (B)
  3. (C)4
  4. (D)
Show answer & solution
Answer: (C) 4
  1. For collinear points the area of the triangle is zero: .
  2. Expanding: .
  3. .
Also asked in: 2026 65/4/1, 2026 65/4/2

Differential of with respect to x is :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (C)
  1. By the chain rule, .
  2. .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q101 markMCQIntegrals

is equal to :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (C)
  1. Put , .
  2. .
  3. .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q111 markMCQIntegrals

If , then the value of k is :

  1. (A)e
  2. (B)
  3. (C)0
  4. (D)
Show answer & solution
Answer: (D)
  1. . Put , ; limits to .
  2. .
  3. So .
Also asked in: 2026 65/4/1, 2026 65/4/2

The sum of the order and the degree of the differential equation is :

  1. (A)not defined
  2. (B)3
  3. (C)1
  4. (D)2
Show answer & solution
Answer: (B) 3
  1. Only appears, so order .
  2. The equation is a polynomial in with highest power 2, so degree .
  3. Sum .
Q131 markMCQLinear Programming

In the graph, the feasible region representing the Linear Programming Problem for maximising objective function , is shaded. If all points on segment AB give max (Z), then which of the following is true ?

Diagram for CBSE 2026 Class 12 Maths question 13
  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (C)
  1. At A(0, 5): . At B(3, 4): .
  2. Maximum at every point of AB means : .
  3. So . (Then , consistent.)
Also asked in: 2026 65/4/1, 2026 65/4/2
Q141 markMCQVector Algebra

Three points A(0, 1, 1), B(2, 0, ) and C(1, 0, 3) form . The ar () is :

  1. (A) sq. units
  2. (B) sq. units
  3. (C) sq. units
  4. (D) sq. units
Show answer & solution
Answer: (A) sq. units
  1. , .
  2. , with magnitude .
  3. Area sq. units.
Also asked in: 2026 65/4/1, 2026 65/4/2
Q151 markMCQVector Algebra

If , then the values of p and q are :

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (B)
  1. Cross product is zero, so the vectors are parallel: .
  2. , .
Also asked in: 2026 65/4/1, 2026 65/4/2

Which of the following is not a Linear Differential Equation ?

  1. (A)
  2. (B)
  3. (C)
  4. (D)
Show answer & solution
Answer: (C)
  1. (A): , linear in y.
  2. (B): , linear in y.
  3. (D): , linear in x.
  4. (C): contains , and contains , so it is not linear.
Also asked in: 2026 65/4/1, 2026 65/4/2
Q171 markMCQLinear Programming

The region represented by the system of inequations , , is :

  1. (A)unbounded in 1 quadrant
  2. (B)bounded in 1 quadrant
  3. (C)unbounded in 2 quadrant
  4. (D)bounded in 2 quadrant
Show answer & solution
Answer: (A) unbounded in 1 quadrant
  1. keeps the region in the first quadrant.
  2. keeps it away from the origin; means .
  3. As x increases, points such as with satisfy all inequations, so the region extends without limit.
  4. Hence it is unbounded in the first quadrant.
Also asked in: 2026 65/4/1, 2026 65/4/2
Q181 markMCQProbability

The probability that a particular item is available in three shops A, B and C is , and respectively. If a person visits all the three shops to buy the item, then what is the probability that it will be available in at least one of the shops ?

  1. (A)
  2. (B)1
  3. (C)
  4. (D)
Show answer & solution
Answer: (A)
  1. Treating availability in the shops as independent, P(not available in any) .
  2. P(available in at least one) .
Q191 markAssertion–ReasonMatrices

Assertion (A) : If A and B are two square matrices such that AB and BA are defined, then it is not necessary that AB = BA.
Reason (R) : Product of two diagonal matrices of same order is commutative.

  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: (B) Both A and R are true, but R is not the correct explanation of A.
  1. Matrix multiplication is not commutative in general, e.g. , give . So A is true.
  2. For diagonal matrices the product is diagonal with entries , so R is true.
  3. R is about a special case and does not explain why AB need not equal BA in general.
Also asked in: 2026 65/4/1, 2026 65/4/2
Q201 markAssertion–ReasonRelations and Functions

Assertion (A) : A function given by is one-one but not onto.
Reason (R) : Since (Codomain), there does not exist in N (Domain) such that .

  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: (C) Assertion (A) is true, but Reason (R) is false.
  1. , so f is one-one.
  2. (or 2) has no pre-image in N, so f is not onto. A is true.
  3. R says that for every no such x exists, which is false: for , .
  4. So A is true but R is false.
Also asked in: 2026 65/4/1, 2026 65/4/2
Q212 marksVery Short AnswerContinuity and Differentiability

Show that the function is continuous at .

Show answer & solution
Answer: Proved.
  1. Put ; as , .
  2. .
  3. equals the limit, so f is continuous at .
Also asked in: 2026 65/4/1, 2026 65/4/2
OR
Q21 (OR) (OR)2 marksVery Short AnswerContinuity and Differentiability

Find whether the function at x = 2 is differentiable or not.

Show answer & solution
Answer: Not differentiable at x = 2.
  1. ; , so f is continuous at 2.
  2. LHD .
  3. RHD .
  4. LHD RHD, so f is not differentiable at .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q222 marksVery Short AnswerVector Algebra

Let two rods placed on the ground be represented by vectors and . Find a vector representing a flag-post of height 5 m that has to be erected perpendicular to both the rods.

Show answer & solution
Answer:
  1. .
  2. Its magnitude is , so a unit vector perpendicular to both is .
  3. Required vector of length 5: (the upward one is taken for the flag-post).
Also asked in: 2026 65/4/1, 2026 65/4/2
OR
Q22 (OR) (OR)2 marksVery Short AnswerVector Algebra

A unit vector is such that it makes an angle with x-axis, with y-axis and an acute angle with z-axis. Find and the components of .

Show answer & solution
Answer: ; components , i.e.
  1. .
  2. ; acute so , .
  3. For a unit vector the components are the direction cosines: .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q232 marksVery Short AnswerApplication of Derivatives

Find the interval(s) for which the function , is increasing.

Show answer & solution
Answer: and
  1. .
  2. or ; at .
  3. So f is increasing on and on .
Q242 marksVery Short AnswerVector Algebra

If in a parallelogram PQRS, and , then find the unit vectors parallel to the diagonals and .

Show answer & solution
Answer: and
  1. , .
  2. , so , .
  3. Unit vectors: and .
Q252 marksVery Short AnswerInverse Trigonometric Functions

Evaluate :

Show answer & solution
Answer:
  1. .
  2. .
  3. .
  4. , so (principal value).
  5. Sum .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q263 marksShort AnswerThree Dimensional Geometry

Find a point on the line at a distance of units from the point (1, 2, 3).

Show answer & solution
Answer: (2, 1, 3) or
  1. Write the line as ; a general point is .
  2. Distance from (1, 2, 3): .
  3. or .
  4. Points: and .
Also asked in: 2026 65/4/1, 2026 65/4/2
OR
Q26 (OR) (OR)3 marksShort AnswerThree Dimensional Geometry

Find the shortest distance between the lines

.

Show answer & solution
Answer: units
  1. Line 1: , .
  2. Line 2: , .
  3. , .
  4. ; .
  5. SD units.
Also asked in: 2026 65/4/1, 2026 65/4/2
Q273 marksShort AnswerMatrices

If , then compute .

Show answer & solution
Answer:
  1. .
  2. , .
  3. .
Q283 marksShort AnswerProbability

In a school, the probability of holding a debate competition is and that of a quiz competition is . In the two participating teams, A has 4 girls and 6 boys and B has 7 girls and 3 boys. If a debate competition is held, the students are selected from team A and for the quiz competition they are selected from team B. If only two students are to be chosen from the teams, then find the probability that one will be a girl and the other a boy.

Show answer & solution
Answer:
  1. Let : debate (team A), : quiz (team B); , . Let G: one girl and one boy chosen.
  2. , .
  3. .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q293 marksShort AnswerLinear Programming

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



Show answer & solution
Answer: Maximum Z = 200 at x = 4, y = 12
  1. Draw , and ; the feasible region is the bounded region right of , above the x-axis and below both lines.
  2. Corner points: (2, 0), (8, 0), (4, 12) [from , ], (2, 13).
  3. Z at these points: 40, 160, 200, 170.
  4. Maximum at .
Q303 marksShort AnswerRelations and Functions

Let and . A function is defined by . Find whether f is one-one and onto.

Show answer & solution
Answer: f is one-one and onto.
  1. One-one: .
  2. . So f is one-one.
  3. Onto: for , solve : , defined since .
  4. (else , impossible), so and .
  5. Hence f is onto; f is one-one and onto.
Also asked in: 2026 65/4/1, 2026 65/4/2
OR
Q30 (OR) (OR)3 marksShort AnswerRelations and Functions

Let n be a fixed positive integer. A relation R is defined in set Z such that is divisible by . Determine if R is an equivalence relation.

Show answer & solution
Answer: Yes, R is an equivalence relation.
  1. Reflexive: , so for all .
  2. Symmetric: if then , so .
  3. Transitive: if and then , so .
  4. Hence R is an equivalence relation.
Also asked in: 2026 65/4/1, 2026 65/4/2
Q313 marksShort AnswerContinuity and Differentiability

If , then find .

Show answer & solution
Answer:
  1. Taking log: .
  2. Differentiating: .
  3. .
  4. .
Also asked in: 2026 65/4/1, 2026 65/4/2
OR
Q31 (OR) (OR)3 marksShort AnswerContinuity and Differentiability

Differentiate with respect to .

Show answer & solution
Answer:
  1. Let , so with , i.e. .
  2. , .
  3. , since .
  4. .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q325 marksLong AnswerIntegrals

Find :

Show answer & solution
Answer:
  1. Let , so .
  2. : . Coefficient of : . Constant: .
  3. Integral .
  4. .
  5. .
Also asked in: 2026 65/4/1, 2026 65/4/2
OR
Q32 (OR) (OR)5 marksLong AnswerIntegrals

Evaluate :

Show answer & solution
Answer:
  1. Put , ; limits to ; .
  2. Integral .
  3. By parts: .
  4. .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q335 marksLong AnswerApplication of Integrals

Using integration, find the area of the region bounded by , , and .

Show answer & solution
Answer: sq. units
  1. The line meets the x-axis at ; it is below the axis on and above on .
  2. Area .
  3. .
  4. .
  5. Area sq. units.
Q345 marksLong AnswerDifferential Equations

Solve the differential equation , when .

Show answer & solution
Answer: , i.e.
  1. Write as , i.e. , linear in x.
  2. I.F. .
  3. .
  4. : , gives , so .
  5. Solution: .
Also asked in: 2026 65/4/1, 2026 65/4/2
OR
Q34 (OR) (OR)5 marksLong AnswerDifferential Equations

Find the general solution of the differential equation
.

Show answer & solution
Answer:
  1. is homogeneous. Put : .
  2. , so .
  3. Put : .
  4. So , i.e. constant.
  5. With : , i.e. .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q355 marksLong AnswerThree Dimensional Geometry

Find the length of the perpendicular drawn from the point P(1, 2, 3) to the line . Also, find the equation of the perpendicular line joining P and the foot of the perpendicular.

Show answer & solution
Answer: Length 7 units; foot (3, 5, 9); line , i.e.
  1. A general point on the line is , so .
  2. : .
  3. Foot ; , length units.
  4. Line PQ: , or .
Q364 marksCase StudyDeterminants

A carpenter needs to design a wooden box in the shape of a cuboid such that the sum of its length and breadth is 3 cm more than its height. Twice of its length, thrice of its breadth and its height add up to 10 cm. Its breadth added to 7 times its height is 1 cm less than 3 times its length.
On the basis of the above information, answer the following questions :
(i) Write the equations representing the various dimensions and express them as the matrix equation AX = B. (1)
(ii) Find if exists. Justify your answer. (1)
(iii) Find . (2)
OR
(iii) Find . (2)

Show answer & solution
Answer: (i) , , ; (ii) Yes, (iii) ; OR
  1. (i) Let length l, breadth b, height h (cm). , , .
  2. So , , : , , .
  3. (ii) , so A is non-singular and exists.
  4. (iii) Cofactors: .
  5. . (This gives , , .)
  6. OR (iii) , so .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q374 marksCase StudyProbability

An NGO organises a charity event in which they decide to distribute woollen caps to protect children from winter. The caps to be distributed are in three separate boxes, Box I has 30 red caps, Box II has 20 red and 10 green caps, and Box III has 30 green caps. The probability that a Box i is selected and a cap picked out is , where i = 1, 2, 3.
Based on the above information, answer the following questions :
A person selects a cap.
(i) What is the probability that he selects a red cap ? (2)
(ii) If he selects a green cap, what is the probability that the cap has come from Box II ? (2)

Show answer & solution
Answer: (i) (ii)
  1. Let : Box i is selected; , , .
  2. (i) , , .
  3. .
  4. (ii) ; .
  5. .
Also asked in: 2026 65/4/1, 2026 65/4/2
Q384 marksCase StudyApplication of Derivatives

At a birthday party, children are being served orange juice in conical cups, as shown in the figure.
Each cup is 15 cm deep and has a radius 5 cm. The juice is being poured into this cup at a rate of 0.1 cm/s.
On the basis of the above information, answer the following questions :
(i) Establish a relation between the height h of the juice in the cup and radius r of the surface of the juice in the cup, if the semi-vertical angle of the cone is . (1)
(ii) At what rate is the juice level in the cup rising when the juice is 6 cm deep ? (1)
(iii) When the juice is 6 cm deep, then find at what rate is the upper surface area of juice increasing ? (2)
OR
(iii) When the juice is 6 cm deep, then find the rate at which the wetted surface area of the cup is increasing. (2)

Diagram for CBSE 2026 Class 12 Maths question 38
Show answer & solution
Answer: (i) , here so (ii) cm/s (iii) cm/s; OR cm/s
  1. (i) In the right triangle formed by the axis, a radius of the juice surface and the slant side, , so . For the cup , so .
  2. (ii) , so .
  3. At : cm/s.
  4. (iii) Upper surface area ; cm/s.
  5. OR (iii) Wetted surface with , so .
  6. cm/s.
Also asked in: 2026 65/4/1, 2026 65/4/2
← 2026 65/4/2 2026 65/5/1 →
Practise smarter: chapter-wise revision, formula sheets and step-by-step NCERT solutions on MonoMath CBSE →