Find fyy (x,y) where f(x,y) = x2y3 + x4y + xe2y
This is the part where you show your attempt. Also use ^ to denote power, I assume x2y3 means x^2 y^3. If you know TeX you can write that as [tex]x^2y^3[/tex]
Try this: replace every x with the constant a... now the equation should look like it is in one variable, y. So what you need now is to find the second derivative with respect to y. Does that make life easier?
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