(x-sinx)/x 当x趋向于0时的极限 当x趋近于0时，limx-sinx/x+sinx怎么算
\u4e3a\u4ec0\u4e48\u5f53x\u8d8b\u8fd1\u4e8e0\u65f6\uff0c(sinx)/x\u7684\u6781\u9650\u7b49\u4e8e1\u89e3\u9898\u8fc7\u7a0b\u5982\u4e0b\uff1a
limsinx\uff08x->0\uff09=0
limx\uff08x->0\uff09=0
\uff08sinx\uff09'=cosx\uff1b(x)'=1
=lim(sinx/x)
=lim(cosx/1)
=cos0
=1
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\u89e3\u9898\u8fc7\u7a0b\u5982\u4e0b\uff1a
\u7531\u91cd\u8981\u6781\u9650lim(x\u21920)sinx/x=1
\u6240\u4ee5\u4e0a\u4e0b\u540c\u9664\u4ee5x
\u539f\u5f0f=lim(x\u21920)(1-sinx/x)/(1+sinx/x)
=(1-1)/(1+1)
=0
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0/0型，
洛必达法则
(x-sinx)'/x'
=(1-cosx)/1
=(1-1)/1
=0
＝（X/X）－（Sinx/x）
X/X＝1
Sinx/x＝1(洛必达法则)（分子分母同时为零，结果等于分子分母各自求导再相除，即cosx/1，在X趋向零时结果等于1）
所以原式＝1－1＝0
洛必达法则
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