推 mutilate : 會了 感謝 09/19 16:44
※ 引述《mutilate (mutilate)》之銘言：
: lim (cosx-1)/sin(xsinx)
: x-->0
: 想不出來
: plz
(cosx-1)/sin(xsinx)
= [xsin(x)]/sin(xsin(x)) * [cos(x) - 1]/[xsin(x)]
= [xsin(x)]/sin(xsin(x)) * [-2sin(x/2)sin(x/2)]/[2xsin(x/2)cos(x/2)]
所以取極限後
= -1/2
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