x²-2x-x+2=0怎么算
问题描述：
x²-2x-x+2=0怎么算
答
x²-2x-x+2 = 0
x²-3x = -2
x²-3x+9/4 = -2+9/4
(x-3/2)² = 1/4
x= ±1/2+3/2
x1 = 2
x2 = 1