(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

[tex]\sqrt{x}+\sqrt{y}= 4[/tex] prove that [tex]y''=\frac{2}{x\sqrt{x}}[/tex]

3. The attempt at a solution

[tex]\frac{dy}{dx}=-\frac{\sqrt{y}}{\sqrt{x}}[/tex]

I tried solving for the second derivative and got

[tex]\frac{d^2y}{dx^2}=-\frac{-x\frac{dy}{dx}-y}{2\sqrt{\frac{y}{x}}x^2}[/tex]

[

Which is wrong if I plug in values.

Anyone sees my error?

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# Homework Help: Double derivative proof

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