Here's the question you clicked on:
Study23
\(\ \large \frac{dy}{dx} e^{-x}+xe^{-x} \) ?
Is this derivative with first term only??
That's not an equation, it's an expression and so in this state is useless
It is totally useful: \[-e^{-x} +x \cdot e^{-x} \implies e^{-x}(x-1)\]
Only if you've got the problem.