Question

已知z=arctany/x求az/ax,az/ay

Answer 1

∂z/∂x

=1/(1+y^2/x^2)*(y/x)'

=x^2/(x^2+y^2)*y*(-1/x^2)

=-y/(x^2+y^2)

∂z/∂y

=1/(1+y^2/x^2)*(y/x)'

=x^2/(x^2+y^2)*(1/x)

=x/(x^2+y^2)