用分式因解法解下列方程(答三个以上的,多答一个给5分)

问题描述:

用分式因解法解下列方程(答三个以上的,多答一个给5分)
(1)4x²-9=0
(2)(2x+1)²-5=0
(3)(3-x)²=4(2x+1)²
(4)2x(2x-3)-4(3-2x)=0
(5)9x²-6x+1=0
(6)2x²-7x+3=0
(7)x²+3x-28=0

(1)4x²-9=0
(2x-3)(2x+3)=0
2x-3=0 2x+3=0
x1=3/2 x= -3/2
(2)(2x+1)²-5=0
(2x+1)²=5
2x+1=±√5
x1=(-1+√5)/2
x2=(-1-√5)/2
(3)(3-x)²=4(2x+1)²
【(3-x)+2(2x+1)】【(3-x)-2(2x+1)】=0
(3x+5)(1-5x)=0
x1= -5/3 x2=1/5
(4)2x(2x-3)-4(3-2x)=0
(2x-3)(2x+4)=0
x1=3/2 x2= -2
(5)9x²-6x+1=0
(3x-1)²=0
3x-1=0
x=1/3
(6)2x²-7x+3=0
(2x-1)(x-3)=0
x1=1/2 x2=3
(7)x²+3x-28=0
(x-4)(x+7)=0
x1=4 x2= -7(2x+3)²=(1-3x)²4x²-4x+1=0x²-8x=0谢谢,给你三十分,行不(2x+3)²=(1-3x)²【(2x+3)-(1-3x)】【(2x+3)+(1-3x)】=0(5x+2)(4-x)=0x1= -2/5x2=44x²-4x+1=0(2x-1)²=02x-1=0x=1/2x²-8x=0x(x-8)=0x1=0x2=8