![](https://static.youtibao.com/asksite/comm/h5/images/m_q_title.png)
[主观题]
设函数u=f(x,y)具有二阶连续偏导数,且满足 , 证明:函数f(x2-y2,2xy)也满足.
设函数u=f(x,y)具有二阶连续偏导数,且满足
,
证明:函数g(x,y)=f(x2-y2,2xy)也满足
查看答案
![](https://static.youtibao.com/asksite/comm/h5/images/solist_ts.png)
设函数u=f(x,y)具有二阶连续偏导数,且满足
,
证明:函数g(x,y)=f(x2-y2,2xy)也满足
设二元函数F(ξ,η)的两个偏导数F'1,F'2不同时为零,u(x,y)满足z=f(x,xy),且u(x,y)具有二阶连续偏导数证明