# Math Help - vector calculus - show that

1. ## vector calculus - show that

Show that if are differentiable,

I can do the exact same past exam question when it's cross product, but can't do this one even though its worth fewer marks!

Starting from the LHS:

But really cannot see anyway of getting anywhere near to the RHS from here!

Could anyone please give me a hint?

2. Originally Posted by hunkydory19
Show that if are differentiable,

I can do the exact same past exam question when it's cross product, but can't do this one even though its worth fewer marks!

Starting from the LHS:

Mr F adds: ${\color{red} + F_x \frac{\partial \phi}{\partial x} + F_y \frac{\partial \phi}{\partial y} + F_z \frac{\partial \phi}{\partial z}}$ ......

But really cannot see anyway of getting anywhere near to the RHS from here!

Could anyone please give me a hint?