algebra
posted by Anil on .
Pa^t and Pe^rt are two forms of the same exponential function.
One would expect to obtain the same answer for f(18).
Explain why you may not get the same answer for f(18) in practice.

Pa^t=Pe^rt
take the ln of each side.
tlna=rt
lna=r
If you don't have ln (a)=r, you cannot get the same answer.