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.

2,216.

Find the length of a side of a rhombus whose diagonals are 6cm and 8cm

A.

8cm

B.

5cm

C.

4cm

D.

3cm

Correct answer is B

The diagonal of a rhombus is a line segment that joins any two non-adjacent vertices.

A rhombus has two diagonals that bisect each other at right angles.

i.e this splits 6cm into 3cm each AND 8cm to 4cm

Using Hyp\(^2\) = adj\(^2\) + opp\(^2\)

Hyp\(^2\) = 3\(^2\) + 4\(^2\)

Hyp\(^2\) = 25

Hyp = 5

∴ Length (L) is 5cm because a rhombus is a quadrilateral with 4 equal lengths

 

2,217.

The angle of a sector of s circle, radius 10.5cm, is 48°, Calculate the perimeter of the sector

A.

8.8cm

B.

25.4cm

C.

25.6cm

D.

29.8cm

Correct answer is D

Length of Arc AB = \(\frac{\theta}{360}\) 2\(\pi\)r

= \(\frac{48}{360}\) x 2\(\frac{22}{7}\) x \(\frac{21}{2}\)

= \(\frac{4 \times 22 \times \times 3}{30}\) \(\frac{88}{10}\) = 8.8cm

Perimeter = 8.8 + 2r

= 8.8 + 2(10.5)

= 8.8 + 21

= 29.8cm

2,218.

At what value of x is the function x\(^2\) + x + 1 minimum?

A.

-1

B.

\(-\frac{1}{2}\)

C.

\(\frac{1}{2}\)

D.

1

Correct answer is B

x\(^2\) + x + 1

\(\frac{dy}{dx}\) = 2x + 1

At the turning point, \(\frac{dy}{dx}\) = 0

2x + 1 = 0

x = -\(\frac{1}{2}\)

2,219.

Find the sum of the first 18 terms of the progression 3, 6, 12......

A.

3(217 - 1)

B.

3(218 - 1)

C.

3(218 + 1)

D.

3(217 - 1)

Correct answer is B

3 + 6 + 12 + .....18thy term

1st term = 3, common ratio \(\frac{6}{3}\) = 2

n = 18, sum of GP is given by Sn = a\(\frac{(r^n - 1)}{r - 1}\)

s18 = 3\(\frac{(2^{18} - 1)}{2 - 1}\)

= 3(2^18 - 1)

2,220.

Find the sum of the first twenty terms of the progression log a, log a2, log a3.....

A.

log a20

B.

log a21

C.

log a200

D.

log a210

Correct answer is D

No explanation has been provided for this answer.