Use variation of parameters followed by separation of variables to solve the following differential equation. Use lower c\displaystyle {c} for the constant of integration

y+y=2xex1+yex\displaystyle {y}'+{y}=\frac{{{2}{x}{e}^{{-{x}}}}}{{{1}+{y}{e}^{{x}}}}



(A) Solution with positive square root coefficient
y(x)=\displaystyle {y}{\left({x}\right)}=  



(B) Solution with negative square root coefficient
y(x)=\displaystyle {y}{\left({x}\right)}=