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.

3,956.

A predator moves in a circle of radius √2 centre (0,0), while a prey moves along the line y = x. If 0 \(\leq\) x \(\leq\) 2, at which point(s) will they meet?

A.

(1,1) only

B.

(1,1) and (1,2)

C.

(0,0) and (1,1)

D.

(√2,√2) only

Correct answer is A

x2 + y2 = (√2)2
x2 + y2 = 2
but y = x

Thus; x2 + x2 = 2
2x2 = 2
x2 = + or - 1

But x2 + y2 = 2
12 + y2 = 2
1 + y2 = 2
y2 = 2 - 1
y2 = 1
y = + or - 1

Thus point (x,y) = (1,1) only.

3,957.

In a regular polygon, each interior angle doubles its corresponding exterior angle. Find the number of sides of the polygon.

A.

8

B.

6

C.

4

D.

3

Correct answer is B

2x + x = 180°, => 3x = 180°, and thus x = 60°

Each exterior angle = 60° but size of ext. angle = 360°/n
Therefore 60° = 360°/n
n = 360°/60° = 6 sides

3,958.

if P and Q are fixed points and X is a point which moves so that XP = XQ, the locus of X is

A.

A straight line

B.

a circle

C.

the bisector of angle PXQ

D.

the perpendicular bisector of PQ

Correct answer is D

No explanation has been provided for this answer.

3,959.

3y = 4x - 1 and Ky = x + 3 are equations of two straight lines. If the two lines are perpendicular to each other, find K.

A.

-4/3

B.

-3/4

C.

3/4

D.

4/3

Correct answer is A

Grad of 3y = 4x - 1
y = 4x/3 - 1/3
Grad = 4/3

Grad of Ky = x + 3
y = x/k + 3/4
Grad = 1/k

Since the two lines are perpendicular,
1/k = -3/4
-3k = 4
k = -4/3

3,960.

An equilateral triangle of side √3cm is inscribed in a circle. Find the radius of the circle.

A.

2/3 cm

B.

2 cm

C.

1 cm

D.

3 cm

Correct answer is C

Since the inscribed triangle is equilateral, therefore the angles at all the points = 60°

Using the formula for inscribed circle, 

2R = \(\frac{a}{\sin A} = \frac{b}{\sin B} = \frac{c}{\sin C}\)

where R = radius of the circle; a, b and c are the sides of the triangle.

⇒ 2R = \(\frac{\sqrt{3}}{\sin 60}\)

 2R = \(\frac{\sqrt{3}}{\frac{\sqrt{3}}{2}}\)

2R = 2

R = 1cm