The question:
Let f(x,y) be a differentiable function at (0,0) that satisfies f(0,0)=0.
Let be a differentiable function at t=0 that satisfies:
and let .
Prove g is differentiable at (0,0) and that .
My try:
We know the two functions are differentiable at (0,0) , hence:
and:
So:
From that point I'm pretty stuck...I can't understand how to continue solving the question...
I'll be delighted to get some guidance
Thanks !