Find the constant aaa such that f(x)=eax+e−2xf(x) = e^{ax} + e^{-2x}f(x)=eax+e−2x has an inflection point at x=0x = 0x=0.
a=2a = 2a=2
a=−2a = -2a=−2
a=0a = 0a=0
a=4a = 4a=4