作者TVBS2100 (濤歌的節目)
看板Math
標題[微積] cosx/(1+sin^2x)
時間Wed May 25 12:34:44 2011
π/2 cosx
∫ ------------dx
0 1+sin^2x
my sol
let sinx = u
then du = cosxdx
π
when x= ---- > u = 1
2
when x= 0 > u = 0
_ 1
1 1 -1 | -1 -1
>∫ -------du > tan u | = tan 1 - tan 0
0 1+u^2 _|
0
=π/4 - 0
=π/4
any problem?
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1F：推 GeeDuTu :很正確啊 05/25 17:07