Taylor Series formula

\(\sum^\infty _{n=0}\frac{f^n a }{n!}(x-a)^n\)

Question 1

\(f(x) = \frac{1}{1-x}=(1-x)^{-1}\)

\(f'(x)=(1-x)^{-2}\)

\(f''(x)=2(1-x)^{-3}\)

\(f'''(x)=6(1-x)^{-4}\)

\(f^4(x)=24(1-x)^{-5}\)

\(f(0)=1\)
\(f'(0) = 1\)
\(f''(0) = 2\)
\(f'''(0) = 6\)
\(f^4(0) = 24\)

\(\sum^\infty _{n=0}x^n\)

Question 2

\(f(x) = e^x\) \(f'(x) = e^x\)
\(f''(x)= e^x\)
\(f'''(x)= e^x\)
\(f^4(x)= e^x\)
    \(f(0)=1\)
\(f'(0) = 1\)
\(f''(0) = 1\)
\(f'''(0) = 1\)
\(f^4(0) = 1\)

\(\sum^\infty _{n=0}\frac{x^n}{n!}\)

Question 3

\(f(x)=ln(1+x)\) \(f'(x) = \frac{1}{1+x}\) \(f''(x) = -\frac{1}{(1+x)^2}\)
\(f'''(x)= 2\frac{1}{(1+x)^3}\)
\(f^4(x)= -6\frac{1}{(1+x)^4}\)

\(f(0)=0\)
\(f'(0) = -1\)
\(f''(0) = 1\)
\(f'''(0) = 2\)
\(f^4(0) = -6\)

\(\sum^\infty _{n=0}(-1)^{n+1}\frac{x^n}{n}\)

Question 4

Taylor series of \(f(x) = x^{1/2}\) does not exist as the function is not differentiable at 0.