求y=cos(根号下x)的导数, cos根号x 求导,求详细方法
\u6c42y=cos\uff08\u6839\u53f7\u4e0bx\uff09\u7684\u5bfc\u6570,u=\u221ax,\u5219u'=1/(2\u221ax)
y=cosu
\u6240\u4ee5
y'=-sinu*u'
=-sin\u221ax/(2\u221ax)
\u4ee4\u221ax=u\uff0ccosu\u7684\u5bfc\u6570\u662f-sinu\uff0c\u221ax\u7684\u5bfc\u6570\u662f1/2\u221ax\uff0c\u518d\u628au=\u221ax\u56de\u4ee3\uff0c\u4e24\u8005\u4e58\u79ef\u5c31\u662fcos\u221ax\u7684\u5bfc\u6570
这是一个复合函数求导。
详情如图所示:
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