# Partial derovative

1. Dec 6, 2011

### leonne

1. The problem statement, all variables and given/known data
This is from a physics problem, but says to evaluate the other three terms in the equation.
Going to just show the first one.

2. Relevant equations
($\theta$ 1/sin$\theta$ d/d$\phi$)($\phi$ d/d$\theta$)

3. The attempt at a solution
in the book they show the solution, but no idea why they did this
($\theta$ 1/sin$\theta$ d/d$\phi$)($\phi$ d/d$\theta$) =
($\theta$ 1/sin$\theta$) ((d($\phi$ /d($\phi$)(d/dθ)+($\phi$ d2/d($\phi$dθ) =
((1/sinθ)$\theta$) (-sinθ r - cosθ$\theta$) d/dθ
=-cotθ d/dθ