What is the general solution for y′=x−yx+yy' = \frac{x-y}{x+y}y′=x+yx−y?
12ln(x2+y2)+arctan(yx)=C\frac{1}{2} \ln(x^2+y^2) + \arctan(\frac{y}{x}) = C21ln(x2+y2)+arctan(xy)=C
x2+y2=Cx^2 + y^2 = Cx2+y2=C
x−y=C(x+y)x-y = C(x+y)x−y=C(x+y)
ln∣x+y∣=C\ln|x+y| = Cln∣x+y∣=C