用适当的方法解下列方程.
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用适当的方法解下列方程.
(1)4x(x-3)-3(3-x)=0;
(2)2x2-3x-6=0(配方法);
(3)(2x-1)2=(3x+2)2;
(4)(x-1)2-5(x-1)+6=0.
(1)4x(x-3)-3(3-x)=0;
(2)2x2-3x-6=0(配方法);
(3)(2x-1)2=(3x+2)2;
(4)(x-1)2-5(x-1)+6=0.
(1)4x(x-3)-3(3-x)=0,
(x-3)(4x+3)=0,
x-3=0,4x+3=0,
x1=3,x2=-
3
4;
(2)2x2-3x-6=0,
2x2-3x=6,
x2-
3
2x=2,
配方得:x2-
3
2x+(
3
4)2=2+(
3
4)2,
(x-
3
4)2=
41
16,
开方得:x-
3
4=±
41
4,
x1=
3+
41
4,x2=
3−
41
4;
(3)(2x-1)2=(3x+2)2,
两边开方得:2x-1=±(3x+2),
解得:x1=-3,x2=-
1
5;
(4)(x-1)2-5(x-1)+6=0,
分解因式得:(x-1-2)(x-1-3)=0,
x-1-2=0,x-1-3=0,
x1=3,x2=4.
(x-3)(4x+3)=0,
x-3=0,4x+3=0,
x1=3,x2=-
3
4;
(2)2x2-3x-6=0,
2x2-3x=6,
x2-
3
2x=2,
配方得:x2-
3
2x+(
3
4)2=2+(
3
4)2,
(x-
3
4)2=
41
16,
开方得:x-
3
4=±
41
4,
x1=
3+
41
4,x2=
3−
41
4;
(3)(2x-1)2=(3x+2)2,
两边开方得:2x-1=±(3x+2),
解得:x1=-3,x2=-
1
5;
(4)(x-1)2-5(x-1)+6=0,
分解因式得:(x-1-2)(x-1-3)=0,
x-1-2=0,x-1-3=0,
x1=3,x2=4.