SOS!求求你们了!

问题描述:

SOS!求求你们了!
75道就够= =

你可真狠要这么多题目
1. 5ax+5bx+3ay+3by
解法:=5x(a+b)+3y(a+b)
=(5x+3y)(a+b)
2. x^3-x^2+x-1
解法:=(x^3-x^2)+(x-1)
=x^2(x-1)+ (x-1)
=(x-1)(x^2+1)
3. x2-x-y2-y
解法:=(x2-y2)-(x+y)
=(x+y)(x-y)-(x+y)
=(x+y)(x-y-1)
bc(b+c)+ca(c-a)-ab(a+b)
=bc(c-a+a+b)+ca(c-a)-ab(a+b)
=bc(c-a)+bc(a+b)+ca(c-a)-ab(a+b)
=bc(c-a)+ca(c-a)+bc(a+b)-ab(a+b)
=(bc+ca)(c-a)+(bc-ab)(a+b)
=c(c-a)(b+a)+b(a+b)(c-a)
=(c+b)(c-a)(a+b).
x^2+3x-40
=x^2+3x+2.25-42.25
=(x+1.5)^2-(6.5)^2
=(x+8)(x-5).
(x^2+x+1)(x^2+x+2)-12时,可以令y=x^2+x,则
原式=(y+1)(y+2)-12
=y^2+3y+2-12=y^2+3y-10
=(y+5)(y-2)
=(x^2+x+5)(x^2+x-2)
=(x^2+x+5)(x+2)(x-1).
(1+y)^2-2x^2(1+y^2)+x^4(1-y)^2
原式=(1+y)^2+2(1+y)x^2(1+y)+x^4(1-y)^2-2(1+y)x^2(1-y)-2x^2(1+y^2)
=[(1+y)+x^2(1-y)]^2-2(1+y)x^2(1-y)-2x^2(1+y^2)
=[(1+y)+x^2(1-y)]^2-(2x)^2
=[(1+y)+x^2(1-y)+2x]·[(1+y)+x^2(1-y)-2x]
=(x^2-x^2y+2x+y+1)(x^2-x^2y-2x+y+1)
=[(x+1)^2-y(x^2-1)][(x-1)^2-y(x^2-1)]
=(x+1)(x+1-xy+y)(x-1)(x-1-xy-y)
x^5+3x^4y-5x^3y^2+4xy^4+12y^5
原式=(x^5+3x^4y)-(5x^3y^2+15x^2y^3)+(4xy^4+12y^5)
=x^4(x+3y)-5x^2y^2(x+3y)+4y^4(x+3y)
=(x+3y)(x^4-5x^2y^2+4y^4)
=(x+3y)(x^2-4y^2)(x^2-y^2)
=(x+3y)(x+y)(x-y)(x+2y)(x-2y)
分解因式m +5n-mn-5m
m +5n-mn-5m= m -5m -mn+5n
= (m -5m )+(-mn+5n)
=m(m-5)-n(m-5)
=(m-5)(m-n)
分解因式bc(b+c)+ca(c-a)-ab(a+b)
bc(b+c)+ca(c-a)-ab(a+b)=bc(c-a+a+b)+ca(c-a)-ab(a+b)
=bc(c-a)+ca(c-a)+bc(a+b)-ab(a+b)
=c(c-a)(b+a)+b(a+b)(c-a)
=(c+b)(c-a)(a+b)
1.(2a-b)²+8ab
2.y²-2y-x²+1
3.x²-xy+yz-xz
4.6x²+5x-4
5.2a²-7ab+6b²
6.(x²-2x)²+2(x²-2x)+1
7.(x²-2x)²-14(x²-2x)-15
8.x²(x-y)+(y-x)
9.169(a+b)²-121(a-b)²
10.(x-3)(x-5)+1
答案:1.(2a-b)²+8ab=(2a+b)²
2.y²-2y-x²+1=(y-1)²-x²=(y-1-x)(y-1+x)
3.x²-xy+yz-xz =x(x-y)-z(x-y)=(x-z)(x-y)
4.6x²+5x-4 =(2x-1)(3x+4)
5.2a²-7ab+6b²=(2a-3b)(a-2b)
6.(x²-2x)²+2(x²-2x)+1 =(x²-2x+1)²=(x-1)^4
7.(x²-2x)²-14(x²-2x)-15 =(x²-2x-15)(x²-2x+1)=(x+3)(x-5)(x-1)²
8.x²(x-y)+(y-x) =(x²-1)(x-y)=(x+1)(x-1)(x-y)
9.169(a+b)²-121(a-b)²
=(14a+14b-11a+11b)(14a+14b+11a-11b)
=(3a+25b)(25a+3b)
10.(x-3)(x-5)+1 =(x-3)²-2(x-3)+1 =(x-3-1)²=(x-4)²
-5a^2+16a=a(16-5a)
8x^2-4x=4x(2x-1)
15p+10p^2=5p(3+2p)
-3x^2y-6xy=-3xy(x+2y)
14m^3n^2-6m^2n^3=2m^2n^2(7m-6n)
27a^2 b^3 c+18ab^2=9ab^2(3abc+2)
18xy^2 z^3+12x^2y^2=6xy^2(3z^3+2x)
8m^2n^2 -6m^3 n^2=2m^2n^2(4-3m)
因式分解3a3b2c-6a2b2c2+9ab2c3=3ab^2 c(a^2-2ac+3c^2)
3.因式分解xy+6-2x-3y=(x-3)(y-2)
4.因式分解x2(x-y)+y2(y-x)=(x+y)(x-y)^2
5.因式分解2x2-(a-2b)x-ab=(2x-a)(x+b)
6.因式分解a4-9a2b2=a^2(a+3b)(a-3b)
7.若已知x3+3x2-4含有x-1的因式,试分解x3+3x2-4=(x-1)(x+2)^2
8.因式分解ab(x2-y2)+xy(a2-b2)=(ay+bx)(ax-by)
9.因式分解(x+y)(a-b-c)+(x-y)(b+c-a)=2y(a-b-c)
10.因式分解a2-a-b2-b=(a+b)(a-b-1)
11.因式分解(3a-b)2-4(3a-b)(a+3b)+4(a+3b)2=[3a-b-2(a+3b)]^2=(a-7b)^2
12.因式分解(a+3)2-6(a+3)=(a+3)(a-3)
13.因式分解(x+1)2(x+2)-(x+1)(x+2)2=-(x+1)(x+2) abc+ab-4a=a(bc+b-4)
(2)16x2-81=(4x+9)(4x-9)
(3)9x2-30x+25=(3x-5)^2
(4)x2-7x-30=(x-10)(x+3)
35.因式分解x2-25=(x+5)(x-5)
36.因式分解x2-20x+100=(x-10)^2
37.因式分解x2+4x+3=(x+1)(x+3)
38.因式分解4x2-12x+5=(2x-1)(2x-5)
39.因式分解下列各式: (1)3ax2-6ax=3ax(x-2) (2)x(x+2)-x=x(x+1) (3)x2-4x-ax+4a=(x-4)(x-a) (4)25x2-49=(5x-9)(5x+9) (5)36x2-60x+25=(6x-5)^2 (6)4x2+12x+9=(2x+3)^2 (7)x2-9x+18=(x-3)(x-6) (8)2x2-5x-3=(x-3)(2x+1) (9)12x2-50x+8=2(6x-1)(x-4)
40.因式分解(x+2)(x-3)+(x+2)(x+4)=(x+2)(2x-1)
41.因式分解2ax2-3x+2ax-3= (x+1)(2ax-3)
42.因式分解9x2-66x+121=(3x-11)^2
43.因式分解8-2x2=2(2+x)(2-x)
44.因式分解x2-x+14 =整数内无法分解
45.因式分解9x2-30x+25=(3x-5)^2
46.因式分解-20x2+9x+20=(-4x+5)(5x+4)
47.因式分解12x2-29x+15=(4x-3)(3x-5)
48.因式分解36x2+39x+9=3(3x+1)(4x+3)
49.因式分解21x2-31x-22=(21x+11)(x-2)
50.因式分解9x4-35x2-4=(9x^2+1)(x+2)(x-2)
51.因式分解(2x+1)(x+1)+(2x+1)(x-3)=2(x-1)(2x+1)
52.因式分解2ax2-3x+2ax-3=(x+1)(2ax-3)
53.因式分解x(y+2)-x-y-1=(x-1)(y+1)
54.因式分解(x2-3x)+(x-3)2=(x-3)(2x-3)
55.因式分解9x2-66x+121=(3x-11)^2
56.因式分解8-2x2=2(2-x)(2+x)
57.因式分解x4-1=(x-1)(x+1)(x^2+1)
58.因式分解x2+4x-xy-2y+4=(x+2)(x-y+2)
59.因式分解4x2-12x+5=(2x-1)(2x-5)
60.因式分解21x2-31x-22=(21x+11)(x-2)
61.因式分解4x2+4xy+y2-4x-2y-3=(2x+y-3)(2x+y+1)
62.因式分解9x5-35x3-4x=x(9x^2+1)(x+2)(x-2)