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→ CNY426W: 分母應該是sin(z-π)的4次方吧 ... 08/13 16:52
推 loveyou999: let x=z-pi變成 lim(x->0)x^4/(sinx)^4*(x+pi)=1*pi 08/13 17:20
推 loveyou999: (sin(x+pi))^4=(-sin(x))^4=(sinx)^4 08/13 17:28
→ tiffany0358: 還是看不太懂 因為還是要羅好幾次 不過謝謝~ 08/14 12:35
→ tiffany0358: 要羅5次才有答案耶~~ 08/14 12:37
推 goshfju: 為何你堅持要用L'Hospital 08/14 14:25
→ goshfju: Hint: sinx/x->1 as x->0 08/14 14:26