设函数z=sin(x^2-2y) 求二阶偏导数3
发布网友
发布时间:2023-11-02 19:37
我来回答
共2个回答
热心网友
时间:2024-12-06 10:02
解:
dz/dx=2xcos(x²-2y)
d²z/d²x
=[2xcos(x²-2y)]'
=2{x'cos(x²-2y)+x[cos(x²-2y)]'}
=2[cos(x²-2y)-xsin(x²-2y)2x]
=2[cos(x²-2y)-2x²sin(x²-2y)]
dz/dy=-2cos(x²-2y)
d²z/d²y
=[-2cos(x²-2y)]'
=-2[cos(x²-2y)]'
=-2[-sin(x²-2y)](-2)
=-4sin(x²-2y)
热心网友
时间:2024-12-06 10:03
对x偏导2xcos(x^2-2y)
对y偏导-2cos(x^2-2y)