UI Post-UTME Mathematics 2024 (Model questions) past questions and answers

21 questions. Try each one, then open the answer to check yourself and read the explanation.

Question 1

Logarithms

Solve the equation: log2(x2 − 5x + 6) = 1

  1. A.x = 1 or 2
  2. B.x = 1 or 4
  3. C.x = 2 or −3
  4. D.x = −1 or 3
Show the answer and explanation

Answer: B (x = 1 or 4)

Explanation

x² − 5x + 6 = 2¹, so x² − 5x + 4 = 0, (x − 1)(x − 4) = 0, x = 1 or 4 (both make the log's argument 2 > 0).

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Question 2

Surds

Let a = √5 + √3. Find the value of a2 − 2√15

  1. A.8
  2. B.16
  3. C.10
  4. D.12
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Answer: A (8)

Explanation

a² = 5 + 2√15 + 3 = 8 + 2√15, so a² − 2√15 = 8.

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Question 3

Polynomials

Find the remainder when x4 + 3x3 − 5x2 + x − 6 is divided by x − 2

  1. A.14
  2. B.6
  3. C.16
  4. D.−3
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Answer: C (16)

Explanation

Remainder = f(2) = 16 + 24 − 20 + 2 − 6 = 16.

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Question 5

Mensuration of Plane Shapes

A sector of a circle with radius 7cm has an angle of 60°. Find the area of the sector

  1. A.50/7 πcm2
  2. B.160/7 πcm2
  3. C.49/6 πcm2
  4. D.14πcm2
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Answer: C (49/6 πcm2)

Explanation

Area = (60/360) × π × 7² = 49π/6 cm².

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Question 6

Mensuration of Solids

A cone has a height of 12cm and a base radius of 5cm. Find the total surface area

  1. A.283cm2
  2. B.204.23cm2
  3. C.78.77cm2
  4. D.142cm2
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Answer: A (283cm2)

Explanation

Slant height l = √(12² + 5²) = 13. Total surface area = πr(l + r) = (22/7) × 5 × 18 ≈ 282.9 ≈ 283 cm².

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Question 7

Trigonometry

Solve for x in the interval 0° ≤ x ≤ 360°, 2 sin x = √3

  1. A.60° only
  2. B.60°, 120°
  3. C.60°, 240°
  4. D.50°, 150°
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Answer: B (60°, 120°)

Explanation

sin x = √3/2, which is positive in the first and second quadrants: x = 60° or 180° − 60° = 120°.

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Question 8

Differentiation

If y = e2x sin x, find dy/dx

  1. A.e2x cos x
  2. B.2e2x sin x
  3. C.ex cos x
  4. D.e2x(2 sin x + cos x)
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Answer: D (e2x(2 sin x + cos x))

Explanation

Product rule: dy/dx = 2e²ˣ sin x + e²ˣ cos x = e²ˣ(2 sin x + cos x).

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Question 9

Measures of Central Tendency

The mean of five numbers is 12. Four of them are 10, 15, 8 and 14. What is the fifth number?

  1. A.20
  2. B.60
  3. C.13
  4. D.17
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Answer: C (13)

Explanation

The five numbers add to 5 × 12 = 60; the four given add to 47, so the fifth is 13.

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Question 10

Fractions, Decimals and Approximation

How many integers between 1 and 500 are divisible by both 3 and 7?

  1. A.23
  2. B.32
  3. C.14
  4. D.17
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Answer: A (23)

Explanation

Such numbers are multiples of 21; 500 ÷ 21 = 23.8, so there are 23.

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Question 11

Progressions

The 5th term of an arithmetic progression is 20 and the 10th term is 40. What is the first term?

  1. A.5
  2. B.4
  3. C.2
  4. D.6
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Answer: B (4)

Explanation

a + 4d = 20 and a + 9d = 40 give 5d = 20, d = 4, so a = 20 − 16 = 4.

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Question 12

Vectors and Transformations

If a = 3i + 4j, find the magnitude of a

  1. A.1
  2. B.7
  3. C.25
  4. D.5
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Answer: D (5)

Explanation

|a| = √(3² + 4²) = √25 = 5.

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Question 13

Permutation and Combination

A committee of 3 is to be formed from 7 people. How many different committees are possible?

  1. A.35
  2. B.42
  3. C.63
  4. D.22
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Answer: A (35)

Explanation

⁷C₃ = (7 × 6 × 5)/(3 × 2 × 1) = 35.

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Question 14

Quadratic Equations

Find the discriminant of the equation x2 + 2x − 3 = 0

  1. A.4
  2. B.12
  3. C.16
  4. D.8
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Answer: C (16)

Explanation

b² − 4ac = 2² − 4(1)(−3) = 4 + 12 = 16.

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Question 15

Integration

integrate ∫(2x + 1)dx

  1. A.x2 + x + c
  2. B.x2 − x + c
  3. C.x2 + 2x + c
  4. D.x2 − 2x + c
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Answer: A (x2 + x + c)

Explanation

∫2x dx = x² and ∫1 dx = x, so the result is x² + x + c.

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Question 16

Variation

If y varies directly as x and inversely as z and when x = 2 and z = 3, y = 4, find y when x = 3 and z = 2

  1. A.6
  2. B.12
  3. C.15
  4. D.9
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Answer: D (9)

Explanation

y = kx/z: 4 = 2k/3 gives k = 6. Then y = 6 × 3/2 = 9.

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Question 17

Circle Theorems

The angle subtended by a diameter at the circumference of a circle is

  1. A.180°
  2. B.90°
  3. C.60°
  4. D.120°
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Answer: B (90°)

Explanation

The angle in a semicircle is a right angle, 90°.

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Question 18

Algebraic Expressions

For what value of x is (x4 + 3x3 − 4x2 + 6)/(x − 5) undefined?

  1. A.15
  2. B.3
  3. C.5
  4. D.1/2
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Answer: C (5)

Explanation

A fraction is undefined when its denominator is zero: x − 5 = 0, x = 5.

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Question 19

Quadratic Equations

If α and β are the solutions to x2 + 3x − 10 = 0, find 1/α + 1/β

  1. A.−3/10
  2. B.3/10
  3. C.−10/3
  4. D.10/3
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Answer: B (3/10)

Explanation

1/α + 1/β = (α + β)/(αβ) = (−3)/(−10) = 3/10.

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Question 21

Differentiation

At what value of x is the function y = x2 − 2x − 3 minimum and what is the minimum value of the function?

  1. A.−1, 4
  2. B.1, −4
  3. C.2, 3
  4. D.1, 5
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Answer: B (1, −4)

Explanation

dy/dx = 2x − 2 = 0 at x = 1, and y(1) = 1 − 2 − 3 = −4.

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Question 22

Triangles and Quadrilaterals

In the figure below |PQ| = |PR| = |PS| and SR̂T = 68°, find QP̂S

Diagram for this question
  1. A.68°
  2. B.112°
  3. C.136°
  4. D.56°
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Answer: C (136°)

Explanation

Triangles PQR and PRS are isosceles, so ∠PRQ = ∠PQR and ∠PRS = ∠PSR. On the straight line at R, ∠PRQ + ∠PRS = 180° − 68° = 112°. Then ∠QPS = (180° − 2∠PRQ) + (180° − 2∠PRS) = 360° − 224° = 136°.

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Question 23

Indices

Find x from the equation 273x + 1/2 = 95x − 1/4

  1. A.3/4
  2. B.2
  3. C.4
  4. D.1/2
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Answer: B (2)

Explanation

Write both as powers of 3: 3^(9x + 3/2) = 3^(10x − 1/2), so 9x + 3/2 = 10x − 1/2 and x = 2.

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