Question

用因式分解法解下列方程 1. x(x-1/2)=x 2. 1/2(x-2)^2+x-2=0 3. 9(2x+3)^2-4

Answer 1

1.x(x-1/2)=x

x(x-1/2)-x=0

x(x-1/2-1)=0

x(x-3/2)=0

x=0或x=3/2

2.1/2(x-2)^2+x-2=0

1/2(x-2)(x-2+2)=0

1/2x(x-2)=0

x=0或x=2

3.9(2x+3)^2-4(2x-5)^2=0

[3(2x+3)+2(2x-5)][3(2x+3)-2(2x-5)]=0

(10x-1)(2x+19)=0

x=1/10或x=-19/2