看板 Grad-ProbAsk 關於我們 聯絡資訊
http://ppt.cc/mDVV 這一題我令 x = 1 + cosz ; y = sinz dx = -sinzdz ; dy = coszdz 代入計算有算出答案 = 2 但是計算稍微花了點時間 我自己計算不熟也是原因拉 但由於這是80題的選擇 想請問有沒有什麼方法能較快速的算出或看出答案呢? -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 111.184.227.135
destinycode:V is a gradient field <=>V is a conservative field 10/19 04:33
destinycode:we assume that V=del[f] 10/19 04:34
destinycode:obviously f=y*x^2+c,where c is a constant 10/19 04:34
destinycode:τ:-π/2 -> π/2 =>R:(1,-1) -> (1,1) 10/19 04:34
destinycode:then SV*dR=f(1,1)-f(1,-1)=2 10/19 04:34
gnsh:謝啦!! 完全沒想到XD 10/19 10:31