- #1

aboutammam

- 10

- 0

I have a question if it possible,

Let X a tangantial vector field of a riemannian manifolds M, and f a smooth function define on M.

Is it true that X(exp-f)=-exp(-f).X(f)

And div( exp(-f).X)=exp(-f)〈gradf, X〉+exp(-f)div(X)?

Thank you