Question

Could someone please help me :)

Answer 1

\[\rm If~x+y=2e^\theta \cos \phi;~x-y=2ie^\theta~\sin \phi\\u~is~a~function~of~x~and~y\\~\\~Prove~that~u^2_\theta+u^2_\phi=4xyu^2_{xy}\]

its partial derivative
second order

Answer 2

Someone can help you. But it doesn't mean they will

Answer 3

@paki @timo86m @dan815 @imqwerty @mathmale @mayankdevnani @kohai