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.

2,301.

Factorize m3 - 2m2 - m + 2

A.

(m2 + 1)(m - 2)

B.

(m - 1)(m + 1)(m + 2)

C.

(m - 2)(m + 1)(m - 1)

D.

(m2 + 2)(m - 1)

Correct answer is C

m3 - 2m2 - m + 2

Let f(m) = m3 - 2m2 - m2 + 2

= f(1)

= 1 - 2 - 2 + 2 = 0

∴ m - 1 is factor \(\frac{m^3 - 2m^2 - m^2 + 2}{m - 1}\)

= m2 - m - 2

= (m - 1)m2 - m - 2

= (m - 1)(m + 1)(m - 2)

2,302.

If g(x) = x2 + 3x + 4, find g(x + 1) - g(x)

A.

(x + 2)

B.

2(x + 2)

C.

(2x + 1)

D.

(x2 + 4)

Correct answer is B

g(x) = x2 + 3x + 4

= g(x + 1) = (x + 1)^2 + 3(x + 1) + 4

= x2 + 1 + 2x + 3x + 3 + 4

= x2 + 5x + 8

g(x + 1) - g(x) = x2 + 5x + 8 - (x2 + 3x + 4)

= x2 + 5x + 8 - x2 + 3x + 4

= 2x + 4

= 2(x + 2)

2,303.

If w varies inversely as \(\frac{uv}{u + v}\) and is equal to 8 when

u = 2 and v = 6, find a relationship between u, v, w.

A.

uvw = 16(u + v)

B.

16ur = 3w(u + v)

C.

uvw = 12(u + v)

D.

12uvw = u + v

Correct answer is C

W \(\alpha\) \(\frac{\frac{1}{uv}}{u + v}\)

∴ w = \(\frac{\frac{k}{uv}}{u + v}\)

= \(\frac{k(u + v)}{uv}\)

w = \(\frac{k(u + v)}{uv}\)

w = 8, u = 2 and v = 6

8 = \(\frac{k(2 + 6)}{2(6)}\)

= \(\frac{k(8)}{12}\)

k = 12

i.e 12 ( u + v) = uwv

2,304.

A car travels from calabar to Enugu, a distance of P km with an average speed of U km per hour and continues to benin, a distance of Q km, with an average speed of Wkm per hour. Find its average speed from Calabar to Benin

A.

\(\frac{(p + q)}{pw + qu}\)

B.

\(\frac{uw(p + q)}{pw + qu}\)

C.

\(\frac{uw(p + q)}{pw}\)

D.

\(\frac{uw}{pw + qu}\)

Correct answer is B

Average speed = \(\frac{total Distance}{Total Time}\)

from Calabar to Enugu in time t1, hence

t1 = \(\frac{P}{U}\) also from Enugu to Benin

t2 \(\frac{q}{w}\)

Av. speed = \(\frac{p + q}{t_1 + t_2}

= p + q * \frac{p}{u} + \frac{q}{w}\)

= p + q x \(\frac{uw}{pw + qu}\)

= \(\frac{uw(p + q)}{pw + qu}\)

2,305.

Evaluate \(\frac{xy^2 - x^2y}{x^2 - xy^1}\) When x = -2 and y = 3

A.

3

B.

-\(\frac{3}{5}\)

C.

\(\frac{3}{5}\)

D.

-3

Correct answer is D

\(\frac{xy^2 - x^2y}{x^2 - xy^1}\)

= \(\frac{(-2)(3)^2 - (-2)^2(3)}{(-2)^2 - (-2)(3)}\)

= \(\frac{-30}{10}\)

= -3