xdy+ydx-(x^2+3x+2)dx=0
设dz(x,y)=xdy+ydx-(x^2+3x+2)dx
∂z/∂y=x,z=xy+g(x),∂z/∂x=y+g‘(x)
又:∂z/∂x=y-(x^2+3x+2)
g‘(x)=-(x^2+3x+2)
g(x)=-(x^3/3+3x^2/2+2x)+C
所以通解为:xy-(x^3/3+3x^2/2+2x)+C=0
xdy+ydx-(x^2+3x+2)dx=0
设dz(x,y)=xdy+ydx-(x^2+3x+2)dx
∂z/∂y=x,z=xy+g(x),∂z/∂x=y+g‘(x)
又:∂z/∂x=y-(x^2+3x+2)
g‘(x)=-(x^2+3x+2)
g(x)=-(x^3/3+3x^2/2+2x)+C
所以通解为:xy-(x^3/3+3x^2/2+2x)+C=0