Question

1、用因式分解法解下列方程: (1)3y^2-5y=0 （2）4x^2=12x (3)x^2+9=-6x (4)9x^2=(x-1)^2

1、用因式分解法解下列方程:

(1)3y^2-5y=0 （2）4x^2=12x (3)x^2+9=-6x (4)9x^2=(x-1)^2 (5) (x-2)(2x-3）=6

（6） x(x-4)= - 4 (7) (2x-1)^2= - 8 (8) (x-2)^2=2x(x-2)

2、解方程 x^2-2√3 x= - 3

求解、求详细答案。比如，

x^3-3x^2-13x+15
=x^3-3x^2+2x-15x+15
=x(x^2-3x+2)-15(x-1)
=x(x-2)(x-1)-15(x-1)
=(x-1)[x(x-2)-15]
=(x-1)[x^2-2x-15]
=(x-1)(x-5)(x+3) 这样的

后天就开学了。跪求啊

Answer 1

(1)y(3y-5)=0 (4)9X^2=(X-1)^2 (6)X^2-4X=-4
y=0或y=5/3 (3X)^2=(X-1)^2 X^2-4X+4=0
(2)4X^2=12X (3X)^2-(X-1)^2=0 (X-2)^2=0
4X^2-12X=0 (3X+X-1)(3X-X+1)=0 X=2
4X(X-3)=0 (4X-1)(2X+1)=0 (7)(2X-1)^2恒不为负，无解
X=0或X=3 X=1/4或X=-1/2 (8)(X-2)^2-2X(X-2)=0 (3)X^2+6X+9=0 (5)先将左边展开 (X-2)(X-2-2X)=0
(X+3)^2=0 2X^2-3X-4X+6=6 (X-2)(-X-2)=0
X=-3 2X^2-7X=0 X=2或X=-2
X(2X-7)=0
X=0或X=7/2

2. x^2-2√3 x+3=0
(X-√3)^2=0
X=√3
打这么多字也不容易，别忘了采纳哦

Answer 2

1) 3y^2-5y=0
解：(3y-5)y=0
y=0或y=5/3

2) 4x^2=12x
解:4x^2-12x=0
4x(x-3)=0
x=0或x=3

(3) x^2+9=-6x
解:x^2+6x+9=0
(x+3)^2=0
x=-3

(4) 9x^2=(x-1)^2
解:(3x)^2-(x-1)^2=0
(3x-x+1)(3x+x-1)=0
(2x+1)(4x-1)=0
x=-1/2或x=1/4

(5) (x-2)(2x-3）=6
解:2x^2-3x-4x+6=6
2x^2-7x=0
(2x-7)x=0
x=0或x=7/2

（6） x(x-4)= - 4
解:x^2-4x+4=0
(x-2)^2=0
x=2

(7) (2x-1)^2= - 8 题目有问题

(8) (x-2)^2=2x(x-2)
解：x^2-4x+4=2x^2-4x
0=x^2-4
0=(x-2)(x+2)
x=2或x=-2

Answer 3

(1)3y^2-5y=0 （2）4x^2=12x (3)x^2+9=-6x
y(3y-5)=0 x^2-3x =x(x-3) =0 x^2+9+6x=(x+3)^2=0
(4)9x^2=(x-1)^2 (5) (x-2)(2x-3）=6 （6） x(x-4)= - 4
9x^2=x^2-2x+1 2x^2-3x-4x+6=6 x^2-4x+4=0
8x^2+2x-1=0 2x^2-7x=0 (x-2)^2=0
(4x-1)(2x+1)=0 x(2x-7)=0
(7) (2x-1)^2= - 8x
4x^2-4x+1=-8x
(2x+1)^2=0 (这一题我觉得题目有错，我改了一下题目)
(8) (x-2)^2=2x(x-2) 2、解方程 x^2-2√3 x= - 3
x^2-4x+4=2x^2-4x x^2-2√3 x+3=0
x^2-4=0 ( x-√3)^2=0 x=√3 或x=-√3
(x+4)(x-4)=0