因式分解计算题20道，要过程，急求，

Answer 1

以下应该够用的了!!

1.(3a－b)2－4(3a－b)(a＋3b)＋4(a＋3b)2＝[3a-b-2(a+3b)]^2=(a-7b)^2
2.(a＋3)2－6(a＋3)＝(a+3)(a-3)
3(x＋1)2(x＋2)－(x＋1)(x＋2)2＝-(x+1)(x+2)
4.abc＋ab－4a＝a(bc+b-4)
5.16x2－81＝(4x+9)(4x-9)
6.9x2－30x＋25＝(3x-5)^2
7.x2－7x－30＝(x-10)(x+3)
8.x2－25＝(x+5)(x-5)
9.x2－20x＋100＝(x-10)^2
10.x2＋4x＋3＝(x+1)(x+3)
11.4x2－12x＋5＝(2x-1)(2x-5)
12.3ax2－6ax＝3ax(x-2)
13.x(x＋2)－x＝x(x+1)
14.x2－4x－ax＋4a＝(x-4)(x-a)
15.25x2－49＝(5x-9)(5x+9)
16.36x2－60x＋25＝(6x-5)^2
17.4x2＋12x＋9＝(2x+3)^2
18.x2－9x＋18＝(x-3)(x-6)
19.2x2－5x－3＝(x-3)(2x+1)
20.12x2－50x＋8＝2(6x-1)(x-4)
21.(x＋2)(x－3)＋(x＋2)(x＋4)＝(x+2)(2x-1)
22.2ax2－3x＋2ax－3＝ (x+1)(2ax-3)
23.9x2－66x＋121＝(3x-11)^2
24.8－2x2＝2(2+x)(2-x)
25.x2－x＋14 ＝整数内无法分解
26.9x2－30x＋25＝(3x-5)^2
27.－20x2＋9x＋20＝(-4x+5)(5x+4)
28.12x2－29x＋15＝(4x-3)(3x-5)
29.36x2＋39x＋9＝3(3x+1)(4x+3)
30.21x2－31x－22＝(21x+11)(x-2)
31.9x4－35x2－4＝(9x^2+1)(x+2)(x-2)
32.(2x＋1)(x＋1)＋(2x＋1)(x－3)＝2(x-1)(2x+1)
33.2ax2－3x＋2ax－3＝(x+1)(2ax-3)
34.x(y＋2)－x－y－1＝(x-1)(y+1)
35.(x2－3x)＋(x－3)2＝(x-3)(2x-3)
36.9x2－66x＋121＝(3x-11)^2
37.8－2x2＝2(2-x)(2+x)
38.x4－1＝(x-1)(x+1)(x^2+1)
39.x2＋4x－xy－2y＋4＝(x+2)(x-y+2)
40.4x2－12x＋5＝(2x-1)(2x-5)
41.21x2－31x－22＝(21x+11)(x-2)
42.3x2－6x＝3x(x-2)
43.49x2－25＝(7x+5)(7x-5)
44.6x2－13x＋5＝(2x-1)(3x-5)
45.x2＋2－3x＝(x-1)(x-2)
46.12x2－23x－24＝(3x-8)(4x+3)
47.(x＋6)(x－6)－(x－6)＝(x-6)(x+5)
48.3(x＋2)(x－5)－(x＋2)(x－3)＝2(x-6)(x+2)
49.9x2＋42x＋49＝(3x+7)^2 。
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希望对你有帮助，不懂还可问，满意请及时采纳！祝你学习进步！o(∩_∩)o

Answer 2

1（x-y)(a-2b+3c)-3(x-y)(2b-a-3c)
=2（x-y)(a-2b+3c)+3(x-y)(a-2b+3c)
=5(x-y)(a-2b+3c)

2.x(a+b-c)-y(-a-b+c)-b+c-a
=x(a+b-c)+y(a+b-c)-(a+b-c)
=(a+b-c)(x+y-1)

3.121(a-b)²-169(a+b)²
=[11(a-b)-13(a+b)][11(a-b)+13(a+b)]
=(11a-11b-13a-13b)(11a-11b+13a+13b)
=(-2a-24b)(24a+2b)
=-4(a+12b)(12a+b)

4.(x+1)^4-2(x+1)^2+1
=[(x+1)^2]^4-2(x+1)^2+1
={(x+1)^2-1]^2
=(x^2+2x+1-1)^2
=(x^2+2x)^2
=x^2(x+2)^2

5.x^2-3x+2=0
(x-1)(x-2)=0
x=1 或 x=2
6.x^2+2x-15=(x+5)(x-3)

7.y^2+4y-5=(y-1)(y+5)
8.m^2-6m+8=(m-2)(m-4)
9.p^2-5p-36=(p-9)(p+4)
10.-x^2+2x+8=-(x-4)(x+2)
11.(x-y)^2-3(x-y)+2=(x-y-1)(x-y-2)
12.0.49x^2-0.04y^2=(0.7x+0.2y)(0.7x-0.2y)
13.-4a^2b^2+4ab-1=-(2ab-1)^2
14.-3a^3x+12ax^3=-3ax(a+x)(a-x)
15.m^3n-2m^2n^2+mn^3=mn(m-n)^2
16.(4x^2-25y^2)÷(2x-5y)=(2x+5y)(2x-5y)÷(2x-5y)=2x+5y
17.(2x^2-2x+1/2)÷(x-1/2)=(1/2)(2x-1)^2÷[(1/2)(2x-1)]=2x-1
18.x^3-2x^2-3x=x(x-3)(x+1)
19.(x-1)(x-2)-6=x^2-3x-4=(x-4)(x+1)
20.64-16a+a^2=(a-8)^2

Answer 3

题目在哪里啊，题目在哪里.........

Answer 4

题目哦？