APEX Calculus Chapter 8.8 Exercise 9

Find a formula for the \(n^{th}\) term of the Taylor Series of f(x), centered at c, by finding the coefficients of the first few powers of x and looking for a pattern.

\(f(x) = e^{-x};\)\(c = 0\)

\(f'(x) = -e^{-x}\)\(f'(0) = -1\)

\(f''(x) = e^{-x}\)\(f''(0) = 1\)

\(f'''(x) = -e^{-x}\)\(f'''(0) = -1\)

\(f^{(4)}(x) = e^{-x}\)\(f^{(4)}(0) = 1\)

\(f(x) = f(a) + \frac{f'(a)}{1!}(x-a) + \frac{f''(a)}{2!}(x-a)^2 + \frac{f'''(a)}{3!}(x-a)^3 + ...\)

\(= 1 + \frac{-1}{1!}x + \frac{1}{2!}x^2 + \frac{-1}{3!}x^3 + \frac{1}{4!}x^4 + ...\)

\(\Sigma^\infty_{n=0} (-1)^{n} \frac{x^n}{n!}\)