- #1

Yegor

- 147

- 1

I have to proof that (∂z/∂x)*x+(∂z/∂y)*y=3*z

I have expressed all partial derivatives, but I got only (∂z/∂x)*x-(∂z/∂y)*y=z

I think that it's impossible at all to solve this problem, because z is arbitrary function as i understand.

Help me please. Where I'm wrong?