推 jacky7987 :log(1-x)=sum_{n=1}^無限 (-1)^{n+1}/n 09/27 22:30
→ jacky7987 :然後用abel limit thm 09/27 22:30
→ jacky7987 :上面打錯了= =" 09/27 22:30
→ suker :泰勒展開式log(1+x) =x-x^2/2+x^3/3-x^4/4+x^5/5-... 09/27 22:31
→ jacky7987 :log(1+x)=sum_{n=1}^無限 (-1)^{n+1}x/n 09/27 22:33
→ jacky7987 :少n次方= =" 09/27 22:34