Jamb Mathematics 1992 Past Questions and Answers

Question 31:

• JAMB 1992

Given that \(\theta\) is an acute angle and sin \(\theta\) = \(\frac{m}{n}\), find cos \(\theta\)

A. \(\frac{\sqrt{n^2 - m^2}}{m}\)
B. \(\frac{\sqrt{(n + m)(n - m)}}{n}\)
C. \(\frac{m}{\sqrt{n^2 - m^2}}\)
D. \(\sqrt{\frac{n}{n^2 - m^2}}\)

Question 32:

• JAMB 1992

Evaluate \(\lim \limits_{x \to 2} \frac{(x - 2)(x^2 + 3x - 2)}{x^2 - 4}\)

A. 7
B. 2
C. 3
D. 4

Question 33:

• JAMB 1992

If y = x sin x, Find \(\frac{d^2 y}{d^2 x}\)

A. 2 cosx - x sinx
B. Sinx + x cosx
C. Sinx - x cosx
D. X sinx - 2 cosx

Question 34:

• JAMB 1992

Ice forms on a refrigerator ice-box at the rate of (4 - 06t)g per minute after t minutes. If initially there are 2g of ice in the box, find the mass of ice formed in 5 minutes

A. 19.5
B. 17.0
C. 14.5
D. 12.5

Question 35:

• JAMB 1992

Obtain a maximum value of the function f(x) x³ - 12x + 11

A. -5
B. -2
C. 2
D. 27