(A)
So you know:
A(t) = the integral of e^(-x) dx from 0 to t
and
V(t) = the integral of Pi*[e^(-x)]^2 dx from 0 to t
Just evaluate the integrals:
A(t) = -e^-t + 1
and
V(t) = -(1/2)*Pi*e^-2x + Pi/2
and then take the limits as t approaches infinity.
(B)
Just put V(t) over A(t) and take the limits.
(C)
I'm not sure what to do here though
Idryg 21:02, 6 October 2008 (UTC)
