The given differential equation is, y′=e−y−x1​dxdy​=e−y−x1​ Write the above equation as, dydx​=e−y−xdydx​+x=e−y Compare with dydx​+Px=Q So, P=1,Q=e−y Therefore, IF​=e∫Pdy=e∫1dy=ey​ The solution of the given differential equation is, x⋅ey=∫ey⋅e−ydy+Cx⋅ey=∫1dy+Cx=e−y(y+C)