求初中数学试题 带答案的！！

1、x^3+2x^2-16x-32(1到4题答案在后面） 2、(a-b)a^6+（b-a)b^6 3、(x+y)(x+y+2xy)+(xy+1)(xy-1)

4、x^4+3x^3-3x^2-12x-4

5、a^3－a^2－2a= a(a^2-a-2)=a(a-2)(a+1)

6、4m^2－9n^2－4m+1=4m^2－4m+1－9n^2=(2m^-1)^2－(3n)^2=(2m-1+3n)(2m-1-3n)

答案：1、x^3+2x^2-16x-32 =x^2(x+2)-16(x+2) =(x^2-16)(x+2) =(x+4)(x-4)(x+2) 2、(a-b)a^6+（b-a)b^6 =(a-b)a^6-(a-b)b^6 =(a-b)(a^6-b^6) =(a-b)(a^3+b^3)(a^3-b^3) =(a-b)(a+b)(a^2-ab+b^2)(a-b)(a^2+ab+b^2) =(a-b)^2(a+b)(a^2-ab+b^2)(a^2+ab+b^2) 3、(x+y)(x+y+2xy)+(xy+1)(xy-1) =(x+y)^2+2xy(x+y)+x^2y^2-1 =[(x+y)+xy]^2-1 =(x+y+xy+1)(x+y+xy-1) =[x(y+1)+(y+1)](x+y+xy-1) =(y+1)(x+1)(x+y+xy-1)

4、x^4+3x^3-3x^2-12x-4

=x^4-4x²+3x³+x²-12x-4 =x²（x+2)(x-2)+3x(x+2)(x-2)+(x+2)(x-2) =(x+2)(x-2)(x²+3x+1)