xy'-xsin(y/x)-y=0letu=y/xdu/dx = (1/x)dy/dx - (1/x^2)ydy/dx = x[du/dx+ (1/x)u]xy'-xsin(y/x)-y=0x^2.[du/dx+ (1/x)u] - xsinu - xu =0x^2.du/dx -xsinu =0∫du/sinu = ∫dx/xln|cscu -cotu | = lnx +C'cscu -cotu = Cxcsc(y/x) -cot(y/x) =Cx