来自侯崇升的问题
.求f(x,y)=xsin(x+y)+ycos(x+y)的二级偏导数
.求f(x,y)=xsin(x+y)+ycos(x+y)的二级偏导数
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2020-06-17 09:14
.求f(x,y)=xsin(x+y)+ycos(x+y)的二级偏导数
.求f(x,y)=xsin(x+y)+ycos(x+y)的二级偏导数
Zyy=-xsin(x+y)-sin(x+y)-sin(x+y)-ycos(x+y)=-2sin(x+y)-xsin(x+y)-ycos(x+y)Zyy=-xsin(x+y)-sin(x+y)-sin(x+y)-ycos(x+y)=-2sin(x+y)-xsin(x+y)-ycos(x+y)