derivitives

Question

The length of a rectangle is given by the function l(t)=6t+5 and its height is given by the function h(t)=the sq root of t, where t is time in seconds and the dimensions are in centimeters.  Find the average rate of change of the area with respect to time

Answer 1

l(t) = 6t + 5

h(t) = t^1/2

 

A(t) = l(t)h(t)

 

The average rate of change of the area is then

 

d/dt[A(t)] = d/dt[l(t)h(t)]

 

 

Use any derivative rule to find the rate of change.