Rate of change - Jamb Mathematics Past Questions and Answers

Question 6:

• JAMB 2001

Find the dimensions of a rectangle of greatest area which has a fixed perimeter p.

A. Square of sides p
B. Square of sides 2p
C. Square of sides (p/2)
D. Square of sides (p/4)

Question 7:

• JAMB 2002

A circle with radius 5cm has its radius increasing at the rate of 0.2m/s. What will be the corresponding increase in the area?

A. 2π
B. 5π
C. π
D. 4π

Question 8:

• JAMB 2005

The radius r of a circular disc is increasing at the rate of 0.5cm/sec. At what rate is the area of the disc increasing when its radius is 6cm?

A. 36 π cm²/sec
B. 18 π cm²/sec
C. 6 π cm²/sec
D. 3 π cm²/sec

Question 9:

• JAMB 2009

If s = (2 + 3t)(5t - 4), find ds/dt when t = 4/5 secs

A. 0 units per sec
B. 15 units per sec
C. 22 unit per sec
D. 26 units per sec

Question 10:

• JAMB 2013

The radius of a circle is increasing at the rate of 0.02cms^-1. Find the rate at which the area is increasing when the radius of the circle is 7cm.

A. 0.75cm²S^-1
B. 0.53cm²S^-1
C. 0.35cm²S^-1
D. 0.88cm²S^-1