- #1

likephysics

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- 2

## Homework Statement

This is not a homework problem, just a question

[tex]\nabla[/tex](A.B) = (B.[tex]\nabla[/tex]) A +(A.[tex]\nabla[/tex])B+Bx([tex]\nabla[/tex]xA)+Ax([tex]\nabla[/tex]xB)

A,B are vectors

## Homework Equations

## The Attempt at a Solution

I can't make sense of the first 2 terms on the right hand side - is (B.[tex]\nabla[/tex])

just div of B?

Also, how do I solve, [tex]\nabla[/tex](e

^{-x}r

^{-2}[tex]\widehat{r}[/tex])

Can I treat the unit vector [tex]\widehat{r}[/tex] as constant?