Question

differentiate h(x,y)=f(xy,x-y)
h'(x,y)=?

Answer 1

with respect to ??

Answer 2

that is question ?? it does not wrt to what :)

Answer 3

\[ h'(x,y) = f'(xy, x-y)\]
let xy =u and x-y = v
find partial differentiation using chain rule

Answer 4

it might with respect to some other independent variable .. like 'z' or 't'