Question

SC

怎麼化簡？
答案是¡

Answer 1

ㄜ

將Z化成極式=cos45°+isin45°
根據棣美弗定理
z^2+z^4+z^6+.........+z^50
=cos90°+isin90°+cos180°+isin180°+cos270°+isin270°+..........+cos2250°+isin2250°
=i

Answer 2

訪客

等式兩邊都先乘(z^2-1)看看