用因式分解解方程(有过程):(1)9y^2=(y-z)^2 (2)(4x-1)^2=(1-5x)^2 (3)x^3-4x^2+4x=0

问题描述:

用因式分解解方程(有过程):(1)9y^2=(y-z)^2 (2)(4x-1)^2=(1-5x)^2 (3)x^3-4x^2+4x=0

9y^2=(y-z)^2
9y^2-(y-z)^2=0
(3y+y-z)(3y-y+z)=0
(4y-z)(2y+z)=0
4y-z=0.2y+z=0
y=z/4,y=-z/2
(2)(4x-1)^2=(1-5x)^2
(4x-1)^2-(1-5x)^2=0
(4x-1+1-5x)(4x-1-1+5x)=0
(-x)(9x-2)=0
-x=0,9x-2=0
x=0,x=2/9
(3)x^3-4x^2+4x=0
x(x^2-4x+4)=0
x(x-2)^2=0
x=0,x-2=0
x=0,x=2
你能明白,赞同