来自顾涛的问题
求z=sin(xy)+cos(的平方)(xy)函数的偏导数~~~求具体步骤
求z=sin(xy)+cos(的平方)(xy)函数的偏导数~~~求具体步骤
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2020-05-21 01:22
求z=sin(xy)+cos(的平方)(xy)函数的偏导数~~~求具体步骤
求z=sin(xy)+cos(的平方)(xy)函数的偏导数~~~求具体步骤
令u=xy,əu/əx=y,əu/əy=x
z=sinu+cos²u
əz/əx=[cosu-sin(2u)]*əu/əx=y[cos(xy)-sin(2xy)]
əz/əy=[cosu-sin(2u)]*əu/əy=x[cos(xy)-sin(2xy)]