How do you find the Taylor series of f(x)=e^xf(x)=ex ?

1 Answer
Sep 21, 2014

Taylor series at x=0x=0 (also called Maclaurin series) for f(x)f(x) is

f(x)=sum_{n=0}^infty{f^{(n)}(0)}/{n!}x^nf(x)=n=0f(n)(0)n!xn.

Since if f(x)=e^xf(x)=ex, then

f(x)=f'(x)=f''(x)=cdots=f^{(n)}(x)=e^x,

so,

f(0)=f'(0)=f''(0)=cdots=f^{(n)}(0)=e^0=1

Hence, the Maclaurin series is

f(x)=sum_{n=0}^infty 1/{n!}x^n=sum_{n=0}^infty x^n/{n!}