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John O' Meara
Aug8-07, 03:42 PM
Given that \frac{dx}{dy} = (\frac{dy}{dx})^{-1}\\ , differentiate throughout with respect to x and show that \frac{d^2x}{dy^2} = \frac{- \frac{d^2y}{dx^2}}{(\frac{dy}{dx})^3}\\.

An attempt: \frac{d^2 x}{dx dy} = \frac{d (\frac{dy}{dx})^{-1}}{dx} \\ .

I need help to get me started. Thanks for the help.

John O' Meara
Aug8-07, 03:55 PM
Sorry for the second post. It wasn't meant to happen.

matness
Aug8-07, 04:22 PM
It is better to start with \frac{d^2x}{dy^2} = \frac{d}{dy}\big(\frac {dx}{dy})

Kummer
Aug8-07, 04:59 PM
I answered your question in your other post.

Dick
Aug8-07, 05:09 PM
I answered your question in your other post.

That's the second time you done this today (at least). The idea of the Homework Forum is NOT to post complete solutions. The idea is to HELP the poster to solve the problem themselves by giving them guidance. Not to do the work for them. With alll due respect, you've been around for a while, hasn't anyone pointed this out to you before?