求导cos<xy>=x的显函数的导数

只求一阶导数,

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对x求导铅裂
-sinxy*(xy)'=1

(xy)'=x'*y+x*y'槐此闭=y+x*y'
所以扒凳y+x*y'=-1/sin(xy)
y'=-[1/sin(xy)+y]/x

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