$f(x,y) = (xy)^2 + (2x^3 - 7y)(lny-e^x)$
I get $df/dx = 2xy^2 + 6x^2lny +e^x(2x^3-7y-6x^2)$ from deriving the first time and then using the chain rule on the second term to get $(6x^2)(lne-e^x)+(2x^3-7y)(e^x)$ and factoring that out to get the second and third terms in my answer.
but wolfram alpha is showing that the last part should be $e^x(-2x^3-6x+7y)$ instead.
What am I doing wrong?
$$f(x,y) = (xy)^2 + (2x^3 - 7y)(lny-e^x)$$
$$df/dx = 2xy^2 + 6x^2(lny -e^x)-e^x(2x^3-7y)$$
$$=2xy^2 + 6x^2lny +e^x(-2x^3+7y-6x^2)$$