Question

A population of bacteria is introduced into a culture. the number of bacteria P can be modeled by P=500(1+4t/(50+t^2 )) where t is time in hours. Find the rate of change in population when t=2 ...?

Answer 1

P(t)=500(1+4t/(50+t^2 ))

P'(t) = 500 [(50+t^2).4 - 4t.2t]/(50+t^2)^2

by the quotient rule

500 (-4t^2 + 200)/(t^2 + 50)^2

Hence

P'(2) = 500 . (-16 + 200)/54^2 ~= 31.6