初中数学因式分解问题
=a^4+2a？+1-a？
=(a？+1)?-a？
=(a？+a+1)(a？-a+1)
(2)2a？-7ab+6b？
=(2a-3b)(a-2b)
(3)3x？+xy-2y？
=(3x-2y)(x+y)
(4)10a？b？+11ab-6
=(2ab+3)(5ab-2)
(5)7a？x-28a(x的五次方)
=7a？(x-4a？)
(6)x？-10x？+16x
=x(x？-10x+16)
=x(x-2)(x-8)
(7)(x？+3倍)？-2(x？+3x)-8
=(x？+3x+2)(x？+3x-4)
=(x+1)(x+2)(x+4)(x-1)
(8)(x-y)？+4xy-1
=x？-2xy+y？+4xy-1
=x？+2xy+y？-1
=(x+y)？-1
=(x+y+1)(x+y-1)
9.x^2 -4xy +4y^2 -x +2y -2
= (x-2y)^2 - (x-2y) -2
=(x-2y + 1)(x-2y-2)
10.x？+ax？+bx？+cx？+abx+bcx+acx+ab
=x？+cx？+abx+abc+bx？+bcx+ax？+acx
=x？(x+c)+ab(x+c)+bx(x+c)+ax(x+c)
=(x+c)[x？+bx+ab+ax]
=(x+c)[x(x+b)+a(x+b)]
=(x+a)(x+b)(x+c)
11.x？-是吗？-y-1/2
=x？-(y？+y+1/4)
=x？-(y+1/2)？
=(x+y+1/2)(x-y-1/2)
12.x的四次方+3x？+6x？-4
=x^4+x？+2x？+2x？+4(x？-1)
=x？(x+1)+2x？(x+1)+(4x-4)(x+1)
=(x+1)(x？+2x？+4x-4)
13.x？-3x？+4
=x？+1-3(x？-1)
=(x+1)(x？-x+1)-(3x-3)(x+1)
=(x+1)(x？-4x+4)
=(x+1)(x-2)？
14.32a[(x^2+2x)^2]-2a
=2a[16(x^2+2x)^2-1]
=2a(4x^2+8x+1)(4x^2+8x-1)
15.16+8(x^2+4x)+(x^2+4x)^2
=(4+x^2+4x)^2
=(x^2+4x+4)^2
=(x+2)^4
16.3x^ny+9x^(n-1)y^2+x^(n+1)/4
=x^(n-1)(3xy+9y^2+x^2/4)
=x^(n-1)(x^2/4+3xy+9y^2)
=x^(n-1)(x/2+3y)^2
=(1/4)[x^(n-1)](x+6y)^2
17.a^4+a？+3a-5
=a？*(a？+a)+3a-5
=3a？+3a-5
=3(a？+a)-5
18.1+x+x(x+1)+x(x+1)^2+x(x+1)^3
=(1+x)+x(x+1)+x(x+1)^2+x(x+1)^3
=(1+x)(1+x)+x(x+1)^2+x(x+1)^3
=(1+x)？(1+x)+x(x+1)^3
=(1+x)？(1+x)
=(1+x)^4
19.(x-y)(2x-2y-3)-2
=(x-y)[2(x-y)-3]-2
=2(x-y) ^2-3(x-y)-2
=[(x-y)-2][2(x-y)+1]
=(x-y-2)(2x-2y+1)。
x2-3xy-10 y2+x+9y-2 =(x-5y+2)(x+2y-1)。
x2-y2+5x+3y+4 =(x+y+1)(x-y+4)。
xy+y2+x-y-2=(y+1)(x+y-2)。
6x 2-7xy-3 y2-xz+7yz-2z 2 =(2x-3y+z)(3x+y-2z)。
a^2+2b^2+3c^2+3ab+4ac+5bc =(a+b+c)(a+2 b+3c)
x^2-8x+7 =(x-1)(x-7)
X^2+8X+7= (x+1)(x+7)
x^2-10x-11 =(x-11)(x+1)
x^2+10X-11=，(x+11)(x-1)
X^+3x-18 =(x+6)(x-3)
x^2+11x+18 =(x+2)(x+9)
x^2-11x+18 =(x-2)(x-9)
x^2+17x-18 =(x+18)(x-1)
x^2-17x-18 =(x-18)(x+1)
xy+6-2x-3y=(x-3)(y-2)
x2(x-y)+y2(y-x)=(x+y)(x-y)^2
2x2-(a-2b)x-ab=(2x-a)(x+b)
a4-9a2b2=a^2(a+3b)(a-3b)
x3+3x2-4=(x-1)(x+2)^2
ab(x2-y2)+xy(a2-B2)=(ay+bx)(ax-by)
(x+y)(a-b-c)+(x-y)(b+c-a)= 2y(a-b-c)
a2-a-b2-b=(a+b)(a-b-1)
(3a-b)2-4(3a-b)(a+3b)+4(a+3b)2=[3a-b-2(a+3b)]^2=(a-7b)^2
(x+1)2(x+2)-(x+1)(x+2)2 =-(x+1)(x+2)
abc+ab-4a=a(bc+b-4)
16x 2-81 =(4x+9)(4x-9)
9x2-30x+25=(3x-5)^2
x2-7x-30=(x-10)(x+3)
x2-25=(x+5)(x-5)
x2+4x+3=(x+1)(x+3)
4x 2-12x+5 =(2x-1)(2x-5)
3ax2-6ax=3ax(x-2)
x(x+2)-x=x(x+1)
x2-4x-ax+4a=(x-4)(x-a)
25x2-49=(5x-9)(5x+9)
36x2-60x+25=(6x-5)^2
4x2+12x+9=(2x+3)^2
x2-9x+18=(x-3)(x-6)
2x2-5x-3=(x-3)(2x+1)
12 x2-50x+8 = 2(6x-1)(x-4)
(x+2)(x-3)+(x+2)(x+4)=(x+2)(2x-1)
2ax 2-3x+2ax-3 =(x+1)(2ax-3)
9x2-66x+121=(3x-11)^2
8-2x2=2(2+x)(2-x)
9x2-30x+25=(3x-5)^2
-20x2+9x+20=(-4x+5)(5x+4)
12 x2-29x+15 =(4x-3)(3x-5)
36x2+39x+9=3(3x+1)(4x+3)
21x 2-31x-22 =(21x+11)(x-2)
9x4-35x2-4=(9x^2+1)(x+2)(x-2)
(2x+1)(x+1)+(2x+1)(x-3)= 2(x-1)(2x+1)
2ax 2-3x+2ax-3 =(x+1)(2ax-3)
x(y+2)-x-y-1 =(x-1)(y+1)
(x2-3x)+(x-3)2=(x-3)(2x-3)
9x2-66x+121=(3x-11)^2
8-2x2=2(2-x)(2+x)
x4-1=(x-1)(x+1)(x^2+1)
x2+4x-xy-2y+4=(x+2)(x-y+2)
4x 2-12x+5 =(2x-1)(2x-5)
21x 2-31x-22 =(21x+11)(x-2)
4x 2+4xy+y2-4x-2y-3 =(2x+y-3)(2x+y+1)
9x5-35x3-4x=x(9x^2+1)(x+2)(x-2)
3x2-6x=3x(x-2)
49x2-25=(7x+5)(7x-5)
6x 2-13x+5 =(2x-1)(3x-5)
x2+2-3x=(x-1)(x-2)
12x2-23x-24=(3x-8)(4x+3)
(x+6)(x-6)-(x-6)=(x-6)(x+5)
3(x+2)(x-5)-(x+2)(x-3)= 2(x-6)(x+2)
9x2+42x+49=(3x+7)^2 .
3a3b2c-6a2b2c2+9ab2c3=3ab^2 c(a^2-2ac+3c^2)
xy+6-2x-3y=(x-3)(y-2)
x2(x-y)+y2(y-x)=(x+y)(x-y)^2
2x2-(a-2b)x-ab=(2x-a)(x+b)
x^3+2x^2-16x-32=(x+2)(x+4)(x-4)
(a-b)a^6+(b-a)b^6=(a-b)^2(a^2+ab+b^2)(a+b)(a^2-ab+b^2)
(x+y)(x+y+2xy)+(xy+1)(xy-1)=(x+1)(y+1)(x+y+xy-1)
x^8+x^7+1 =(x^2+x+1)(x^6-x^4+x^3-x+1)
x^8+x^6+x^4+x^2+1 =(x^4+x^3-x+1)(x^4+x^3+x^2+x+1)
x^2-20x+100=(x-10)^2
x^2-3x+2=(x-1)(x-2)
x^2-2x-15=(x+3)(x-5)
x^2+2x-15=(x-3)(x+5)
x^2-7x+12=(x-3)(x-4)
x^2-7x-30=(x+3)(x-10)
x^2+2x-3=(x-1)(x+3)
x^2-16x+64=(x-8)^2
x^2-9x+20=(x-4)(x-5)
x^2-6x+8=(x-2)(x-4)
x^2-6x-7=(x-7)(x+1)
给分。