20道初二因式分解题目,急!
2个回答

1.若2x3+3x2+mx+1为x+1的倍式,则m=

2.因式分解3a3b2c-6a2b2c2+9ab2c3=

3.因式分解xy+6-2x-3y=

4.因式分解x2(x-y)+y2(y-x)=

5.因式分解2x2-(a-2b)x-ab=

6.因式分解a4-9a2b2=

7.若已知x3+3x2-4含有x-1的因式,试分解x3+3x2-4=

8.因式分解ab(x2-y2)+xy(a2-b2)=

9.因式分解(x+y)(a-b-c)+(x-y)(b+c-a)=

10.因式分解a2-a-b2-b=

11.因式分解(3a-b)2-4(3a-b)(a+3b)+4(a+3b)2=

12.因式分解(a+3)2-6(a+3)=

13.因式分解(x+1)2(x+2)-(x+1)(x+2)2=

14.若2×4×(32+1)×(34+1)×(38+1)×(316+1)=3n-1,求n= .

15.利用平方差公式,求标准分解式4891= .

16.2x+1是不是4x2+5x-1的因式?答:.

17.若6x2-7x+m是2x-3的倍式,则m=

18.x2+2x+1与x2-1的公因式为 .

19.若x+2是x2+kx-8的因式,求k= .

20.若4x2+8x+3是2x+1的倍式请因式分解4x2+8x+3= .

21.2x+1是4x2+8x+3的因式,请因式分解4x2+8x+3= .

22.(1)x+2 (2)x+4 (3)x+6 (4)x-6 (5)x2+2x3+24 上列何者x2-2x-24的因式 (全对才给分)

23.因式分解下列各式:

(1)abc+ab-4a= .

(2)16x2-81= .

(3)9x2-30x+25= .

(4)x2-7x-30= .

24.若x2+ax-12=(x+b)(x-2),其中a、b均为整数,则ab= .

25.请将适当的数填入空格中:x2-16x+ =(x- )2.

26.因式分解下列各式:

(1)xy-xz+x= ;(2)6(x+1)-y(x+1)=

(3)x2-5x-px+5p= ;(4)15x2-11x-14=

27.设7x2-19x-6=(7x+a)(bx-3),且a,b为整数,则2a+b=

28.利用乘法公式展开99982-4= .

29.计算(1.99)2-4×1.99+4之值为 .

30.若x2+ax-12可分解为(x+6)(x+b),且a,b为整数,则a+b= .

31.已知9x2-mx+25=(3x-n)2,且n为正整数,则m+n= .

32.若2x3+11x2+18x+9=(x+1)(ax+3)(x+b),则a-b= .

33.2992-3992=

34.填入适当的数使其能成为完全平方式4x2-20x+ .

35.因式分解x2-25= .

36.因式分解x2-20x+100= .

37.因式分解x2+4x+3= .

38.因式分解4x2-12x+5= .

39.因式分解下列各式:

(1)3ax2-6ax= .

(2)x(x+2)-x= .

(3)x2-4x-ax+4a= .

(4)25x2-49= .

(5)36x2-60x+25= .

(6)4x2+12x+9= .

(7)x2-9x+18= .

(8)2x2-5x-3= .

(9)12x2-50x+8= .

40.因式分解(x+2)(x-3)+(x+2)(x+4)= .

41.因式分解2ax2-3x+2ax-3= .

42.因式分解9x2-66x+121= .

43.因式分解8-2x2= .

44.因式分解x2-x+14 = .

45.因式分解9x2-30x+25= .

46.因式分解-20x2+9x+20= .

47.因式分解12x2-29x+15= .

48.因式分解36x2+39x+9= .

49.因式分解21x2-31x-22= .

50.因式分解9x4-35x2-4= .

51.因式分解(2x+1)(x+1)+(2x+1)(x-3)= .

52.因式分解2ax2-3x+2ax-3= .

53.因式分解x(y+2)-x-y-1= .

54.因式分解(x2-3x)+(x-3)2= .

55.因式分解9x2-66x+121= .

56.因式分解8-2x2= .

57.因式分解x4-1= .

58.因式分解x2+4x-xy-2y+4= .

59.因式分解4x2-12x+5= .

60.因式分解21x2-31x-22= .

61.因式分解4x2+4xy+y2-4x-2y-3= .

62.因式分解9x5-35x3-4x= .

63.因式分解下列各式:

(1)3x2-6x= .

(2)49x2-25= .

(3)6x2-13x+5= .

(4)x2+2-3x= .

(5)12x2-23x-24= .

(6)(x+6)(x-6)-(x-6)= .

(7)3(x+2)(x-5)-(x+2)(x-3)= .

(8)9x2+42x+49= .

64.9x2-30x+k可化为完全平方式(3x+a)2,则k= a= .

65.若x2+mx-15可分解为(x+n)(x-3),m、n皆为整数,则m= n= .

66.求下列各式的和或差或积或商.

(1)(6512 )2-(3412 )2= .

(2)(7913 )2+2×7913 ×23 +49 = .

(3)1998×0.48-798×0.48-798×0.52+1998×0.52= .

67.因式分解下列各式:

(1)(x+2)-2(x+2)2= .

(2)36x2+39x+9= .

(3)2x2+ax-6x-3a= .

(4)22x2-31x-21= .

68.利用平方差,和的平方或差的平方公式,填填看

(1)49x2-1=( +1)( -1)

(2)x2+26x+ =(x+ )2

(3)x2-20x+ =(x- )2

(4)25x2-49y2=(5x+ )(5x- )

(5) -66x+121=( -11)2

69.利用公式求下列各式的值

(1)求5992-4992= (2)求(7512 )2-(2412 )2=

(3)求392+39×22+112= (4)求172-34×5+52=

(5)若2x+5y=13 +7 ,x-4y=7 -13 求2x2-3xy-20y2=

70.因式分解3ax2-6ax= .

71.因式分解(x+1)x-5x= .

72.因式分解(2x+1)(x-3)-(2x+1)(x-5)=

73.因式分解xy+2x-5y-10=

74.因式分解x2y2-x2-y2-6xy+4= .