>>474
(1)y^2=x^4/2+C, y=√(x^4/2+1)
(2)y=Ce^(sin(x)), y=e^(sin(x))
(3)y/(y-1)=Ce^x, y=3/(3-2*e^(-x))
(4)y=C/x+1, y=-1/x+1