Mathematics questions and answers

Mathematics Questions and Answers

How good are you with figures and formulas? Find out with these Mathematics past questions and answers. This Test is useful for both job aptitude test candidates and students preparing for JAMB, WAEC, NECO or Post UTME.

3,806.

Find the remainder when 3x3 + 5x2 - 11x + 4 is divided by x + 3

A.

-4

B.

4

C.

1

D.

-1

Correct answer is C

x = -3
substitute x = -3 in 3x3 + 5x2 - 11x + 4
3(-3)3 + 5(-3)2 - 11(-3) + 4
-81 + 45 + 33 + 4
-81 + 82
= 1

3,807.

If the operation * on the set of integers is defined by P * Q = \(\sqrt{PQ}\), find the value of 4 * ( 8 * 32).

A.

8

B.

3

C.

16

D.

4

Correct answer is A

\(P\times Q=\sqrt{PQ}\\4\times(8\times32)=4\times\sqrt{8\times32}\\=4\times\sqrt{256}\\=4\times16\\=\sqrt{4\times16}\\=\sqrt{64}\\=8\)

3,808.

Given that the first and forth terms of G.P are 6 and 162 respectively, find the sum of the first three terms of the progression

A.

27

B.

8

C.

78

D.

48

Correct answer is C

\(a=6, U_4 = 162\\U_4 = ar^{4-1}\\U_4 = ar^3\\162 = 6(r)^3\\r^3 = 27\\r=\sqrt[3]{27}\\r=3\\S_4 = \frac{a(r^{n}-1)}{r-1}\\=\frac{6(3^{3}-1)}{3-1}\\=\frac{6(27-1)}{2}\\=3\times26\\=78\)

3,809.

What are the integer values of x which satisfy the inequality -1 < 3 -2x \(\leq\) 5?

A.

-1. 0, 1, 2

B.

-2, 1, 0 , -1

C.

0, 1, 2

D.

-1, 0, 1

Correct answer is D

-1 < 3 -2x and 3 - 2x \(\leq\) 5
2x < 3 + 1 and -2x \(\leq\) 5 - 3
2x < 4 and -2x \(\leq\) 2
x < 2 and x \(\geq\) 2/-2 = x \(\geq\) -1
If -1 \(\leq\) x < 2
it implies that x = -1, 0, 1

3,810.

y is inversely proportional to x and y = 4 when x = 1/2. Find x when y = 10.

A.

2.5

B.

10

C.

1/5

D.

1/10

Correct answer is C

y ∝ 1/x
y = K/x
K = xy
K = (1/2) * 4 ( when y = 4 and x = 1/2)
K = 2
∴y = 2/x
10 = 2/x (when y = 10)
10x = 2
x = 2/10
x = 1/5