you know
A = π r^2
replace r with 2t^2 + 1
and expand
differentiate to find the rate of change
plug in t = 2
The radius, r cm, of a circle at time t seconds is given by r = 2t 2 + 1. Express its
area, A cm2 , in terms of t and find the rate of change of the area at the instant when
t=2. (Leave your answer in terms of p )
1 answer