[積分] 求助!
r
∫----------------------------------- dr
[ r^2 + h^2 - rh*2^(1/2) ]^(1/2)
答案是
[h^2+r^2-rh*2^(1/2)]^(1/2)
+h/2^(1/2)*ln[2(h^2+r^2-rh*2^(1/2))^(1/2)+2r-h*2^(1/2)]
我用代數變換去算(u=r-h/2^(1/2)),可是不知道為甚麼,ln[]的裡面少了兩倍
[h^2+r^2-rh*2^(1/2)]^(1/2)
+h/2^(1/2)*ln[(h^2+r^2-rh*2^(1/2))^(1/2)+r-h/2^(1/2)]
屢試不爽,希望有人為我解惑一下,謝謝!
(跟號2打起來好麻煩= =)
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10/27 00:49, , 1F
10/27 00:49, 1F
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