(x+1)(x+1)-(x-1)(1-x)=6 求x的解 (x-2)(2x+1)=(2x+1)(x+1) 用因式分解解方程
问题描述:
(x+1)(x+1)-(x-1)(1-x)=6 求x的解 (x-2)(2x+1)=(2x+1)(x+1) 用因式分解解方程
答
(x+1)(x+1)-(x-1)(1-x)=6
(x+1)^2 +(x-1)^2 = 6
2x^2+2 = 6
x^2=2
x1=-√2,x2=√2
(x-2)(2x+1)=(2x+1)(x+1)
(x-2)(2x+1)-(2x+1)(x+1)= 0
(2x+1)(x-2-x-1)= 0
(2x+1)(-3)= 0
2x+1=0
x=-1/2