推 OldChuang :(b)n roots 03/10 14:15
推 OldChuang :(a)x用cos(t) on[0,pi] 03/10 14:18
→ OldChuang :(c)和b左法相同 只是看他+-1得點 03/10 14:19
→ handsomepow :t=arcos(x), x=cos(t) t on[0,pi] 這樣變換嗎 03/10 14:35
推 OldChuang :對 然後用數學歸納法 03/10 14:43
→ handsomepow :我先寫看看 感謝 03/10 14:45