Posted by Jacob on .
Under a set of controlled laboratory conditions, the size of the population of a certain bacteria culture at time t (in minutes) is described by the following function.
P=f(t)=3t^2+2t+1
Find the rate of population growth at t = 9 min.

Applied Calculus...... 
Steve,
f'(t) = 6t+2, so
f'(9) = ?