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设z=e^xysin(x+y).计算dz.要直接能抄的

题目详情
设z=e^xysin(x+y).计算dz.要直接能抄的
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答案和解析
是否求函数z=e^xy*cos(x+y)的全微分dz
z=e^xy*cos(x+y)
Z'x=ye^xycos(x+y)-e^xysin(x+y)
Z'y=xe^xycos(x+y)-e^xysin(x+y)
故dZ=[ye^xycos(x+y)-e^xysin(x+y)]dx+[xe^xycos(x+y)-e^xysin(x+y)]dy