U(x,y)=x1+x+yU(x,y) = \dfrac{x}{1+x} + yU(x,y)=1+xx+y, px=pyp_x = p_ypx=py. Then:
x>0x > 0x>0, y=0y = 0y=0.
x=0x = 0x=0, y>0y > 0y>0.
x>0x > 0x>0, y>0y > 0y>0.
x=y=0x = y = 0x=y=0.
