八年级因式分解题,全部做出来加10分

来源:百度知道 编辑:UC知道 时间:2024/05/17 09:07:01
注明:^n表示某个数的n次方。
1、3(y-x)^2+2(x-y)
2、10a(x-y)^2-5b(y-x)
3、289(2x+y)^2-144(x-2y)^2
4、4(x-y)^2(x+y)-6(y-x)^3
5、a^2-b^2-2b-1
6、361(2x+y)^2-121(x-2y)^2
7、9a^2-6a+1
(要求写出主要解题步骤)

3(y-x)^2+2(x-y)
=(x-y)[3(x-y)+2]
=(x-y)(3x-3y+2)

2、10a(x-y)^2-5b(y-x)
=10a(x-y)^2+5b(x-y)
=5(x-y)[2a(x-y)+b]
=5(x-y)(2ax-2ay+b)

3、289(2x+y)^2-144(x-2y)^2
=[17(2x+y)+12(x-2y)][17(2x+y)-12(x-2y)]
=(46x-7y)(22x+41y)

4、4(x-y)^2(x+y)-6(y-x)^3
=4(x-y)^2(x+y)+6(x-y)^3
=2(x-y)^2(2x+2y+3x-3y)
=2(x-y)^2(5x-y)

5、a^2-b^2-2b-1
=a^2-(b^2+2b+1)
=a^2-(b+1)^2
=(a+b+1)(a-b-1)

6、361(2x+y)^2-121(x-2y)^2
=[19(2x+y)+11(x-2y)][19(2x+y)-11(x-2y)]
=(49x-3y)(27x+41y)

7、9a^2-6a+1
=(3a-1)^2

1:3(y-x)^2+2(x-y)
=3(x-y)(x-y)+2(x-y)
=(3x-3y+2)(x-y)

2:10a(x-y)^2-5b(y-x)
=10a(y-x)(y-x)-5b(y-x)
=5(2ay-2ax-b)(y-x)

3:289(2x+y)^2-144(x-2y)^2
=17^2*(2x+y)^2-12^2*(x-2y)^2
=(34x+17y+12x-24y)(34x+17y-12x+24y)
=(46x-7y)(22x+41y)

4:4(x-y)^2*(x+y)-6(y-x)^3
=(x-y)^2*(4x+4y-6y+6x)
=(x-y)^2*(10x-