Proving Vector Identity in Cartesian Coordinates

[QuantumDefect]

Hello, I need some help on this vector identity. I am supposed to prove that Del Dot (Del(g(r)))=(2/r){dg(r)/dr}+(d^2g(r)/dr^2). Using Cartesian Coordinates. Any help would be GREATLY appreciated> :)

 

[robphy]

How is r related to your Cartesian coordinates?
Do you know the chain rule?

 

[QuantumDefect]

r^2=x^2+...?


I think that's what I have to do! I was using r=x*x_hat+... Ill try that, thanks!