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.

296.

Find the derivative of the function y = 2x\(^2\)(2x - 1) at the point x = -1?

A.

18

B.

16

C.

-4

D.

-6

Correct answer is B

y = 2x\(^2\)(2x - 1)
y = 4x\(^3\) - 2x\(^2\)
dy/dx = 12x\(^2\) - 4x
at x = -1
dy/dx = 12(-1)\(^2\) - 4(-1)
= 12 + 4
= 16

297.

The ratio of the length of two similar rectangular blocks is 2 : 3. If the volume of the larger block is 351cm\(^3\), then the volume of the other block is?

A.

234.00 cm3

B.

526.50 cm3

C.

166.00 cm3

D.

687cm3

Correct answer is A

Let x represent total vol. 2 : 3 = 2 + 3 = 5

\(\frac{3}{5}\)x = 351

x = \(\frac{351 \times 5}{3}\)

= 585

Volume of smaller block = \(\frac{2}{5}\) x 585

= 234.00cm\(^3\)

298.

Find the value of p if the line which passes through (-1, -p) and (-2,2) is parallel to the line 2y+8x-17=0?

A.

\(\frac{-2}{7}\)

B.

\(\frac{7}{6}\)

C.

\(\frac{-6}{7}\)

D.

2

Correct answer is D

Line:  2y+8x-17=0 

recall y = mx + c

2y = -8x + 17

y = -4x  + \(\frac{17}{2}\)

Slope m\(_1\) = 4

parallel lines: m\(_1\). m\(_2\) = -4

where Slope ( -4) = \(\frac{y_2 - y_1}{x_2 - x_1}\) at points (-1, -p) and (-2,2)

-4( \(x_2 - x_1\) ) = \(y_2 - y_1\) 

-4 ( -2 - -1) = 2 - -p

p = 4 - 2 = 2

299.

A trapezium has two parallel sides of lengths 5cm and 9cm. If the area is 91cm\(^2\), find the distance between the parallel sides

A.

13 cm

B.

4 cm

C.

6 cm

D.

7 cm

Correct answer is A

Area of Trapezium = 1/2(sum of parallel sides) * h
91 = \(\frac{1}{2}\) (5 + 9)h

cross multiply
91 = 7h
h = \(\frac{91}{7}\)
h = 13cm

300.

Determine the maximum value of y=3x\(^2\) + 5x - 3

A.

6

B.

0

C.

2

D.

No correct option

Correct answer is D

y=3x\(^2\) + 5x - 3

dy/dx = 6x + 5

as dy/dx = 0

6x + 5 = 0

x = \(\frac{-5}{6}\)

Maximum value: 3 \( ^2{\frac{-5}{6}}\)  + 5 \(\frac{-5}{6}\) - 3

3 \(\frac{75}{36}\) - \(\frac{25}{6}\) - 3

Using the L.C.M. 36

= \(\frac{25 - 50 - 36}{36}\)

= \(\frac{-61}{36}\)

No correct option