Re: [微積] 複變積分一問

看板Math作者 (狐狸)時間15年前 (2011/03/11 01:22), 編輯推噓0(009)
留言9則, 2人參與, 最新討論串3/3 (看更多)
不好意思 我想再請問一題複變函數的積分 題目如下 ∫( x + i2y ) dz, C: 由(0,0)至(2.4)之直線. C 答案: -14 + 12i 還請版友指點一下 謝謝各位 -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 59.116.128.139

03/11 10:04, , 1F
C: (0,0) 到 (2,4) 的直線 → y = 2x, 0 <= x <= 2
03/11 10:04, 1F

03/11 10:04, , 2F
x + i2y = x + i4x = (1+4i)x
03/11 10:04, 2F

03/11 10:04, , 3F
dz = dx + idy = dx + 2idx = (1+2i)dx
03/11 10:04, 3F

03/11 10:05, , 4F
原積分 =∫(1+4i)(1+2i)xdx, 0 <= x <= 2
03/11 10:05, 4F

03/11 10:05, , 5F
|2
03/11 10:05, 5F

03/11 10:05, , 6F
= (-7+6i)x^2/2| = (-7+6i)*2 = -14+12i
03/11 10:05, 6F

03/11 10:05, , 7F
|0
03/11 10:05, 7F

03/11 23:14, , 8F
謝謝a大解答..我想請問一下說z = x + iy 跟積分內
03/11 23:14, 8F

03/11 23:14, , 9F
x + i2y 是沒有關係的嗎?
03/11 23:14, 9F
文章代碼(AID): #1DUGZ2P3 (Math)
文章代碼(AID): #1DUGZ2P3 (Math)