应该是方程组吧x^2-2y=2..(1)x^2-3xy+y=1..(2)(1)得到,-2y=2-x^2,2y=x^2-2,y=0.5x^2-1代入(2),x^2-3x*(0.5x^2-1)+0.5x^2-1=1x^2-1.5x^3-3x+0.5x^2-1-1=0-1.5x^3+1.5x^2-3x-2=03x^3-3x^2+6x+4=0...你题目正确么?...