함수 $f \left (x \right) = \ln \left (2-x \right)$ 를 멱급수로 나타내면?

• ①$\displaystyle - \sum _ {n=1} ^ {\infty} \frac{x^n} {n2^ {n+1}} + \ln 2$
• ②$\displaystyle - \sum _ {n=0} ^ {\infty} \frac{x^ {n+1}} {\left (n+1 \right) 2^ {n+1}} + \ln 2$
• ③$\displaystyle - \sum _ {n=0} ^ {\infty} \frac{x^n} {\left (n+1 \right) 2^n} + \ln 2$
• ④$\displaystyle - \sum _ {n=1} ^ {\infty} \frac{x^n} {n2^ {n+2}} + \ln 2$
• ⑤$\displaystyle - \sum _ {n=0} ^ {\infty} \frac{x^ {n+1}} {\left (n+1 \right) 2^n} + \ln 2$