Question

分解因式题

北师大初二数学
p56习题2.2
(1)a^2-81
(2）36-x^2
3 1-16b^2
4 m^2-9n^
5 0.25q^2-121p^2
6 169x^2-4y^2
7 9a^2p^2-b^2q^2
8 449a^2-x^2y^

Answer 1

a^2-81=(a-9)(a+9)

36-x^2=(6-x)(6+x)

1-16b^2=(1-4b)(1+4b)

m^2-9n^2=(m-3n)(m+3n）

0.25q^2-121p^2=(0.5q-11p)(0.5q+11p)

169x^2-4y^2=(13x-2y)(13x+2y)

9a^2p^2-b^2q^2=(3ap-bq)(3ap+bq)

49a^2-x^2y^2=(7a-xy)(7a+xy)

(m+n)^2-N^2=(m+n+N)(m+n-N)

49(a-b)^2-16(a+b)^2=(7a-7b-4a-4b)(7a-7b+4a+4b)=(3a-11b)(11a-3b)

(2x+y)^3-(x+2y)^2=(2x+y+x+2y)(2x+y-x-2y)=3(x+y)(x-y)

(x^2+y^2)^2-x^2 y^2=(x^2+y^2+xy)(x^+y^2-xy)

3ax^2-3ay^4=3a(x+y^2)(x-y^2)

p^4-1=(p^2-1)(p^2+1)=(p-1)(p+1)(p^2+1)

Answer 2

(1)a^2-81
=(a-9)(a+9)

(2）36-x^2
=(6-x)(6+x)

3 1-16b^2
=(1-4b)(1+4b)

4 m^2-9n^2
=(m-3n)(m+3n）

5 0.25q^2-121p^2
=(0.5q-11p)(0.5q+11p)

6 169x^2-4y^2
=(13x-2y)(13x+2y)

7 9a^2p^2-b^2q^2
=(3ap-bq)(3ap+bq)

8 49a^2-x^2y^2
=(7a-xy)(7a+xy)

追问

（m+n)^2-N^2

49(a-b)^2-16(a+b)^2

(2x+y)^3-(x+2y)^2

(x^2+y^2)^2-x^2 y^2

3ax^2-3ay^4

p^4-1
谢谢~

Answer 3

1.(a+9)(a-9)
2.(6+x)(6-x)
3.(1+4b)(1-4b)
4.(2m+3n)(2m-3n)
5.(0.5q+11p)(0.5q-11p)
6.(13x+2y)(13x-2y)
7.(3ap+bq)（3ap-bq）
8.(√449a+xy)(√449a-xy)
谢谢……

Answer 4

(1)a^2-81=(a+9)(a-9)
(2)36-x^2=(6+x)(6-x)
3 1-16b^2=(1+4b)(1-4b)
4 m^2-9n^2=(m+3n)(m-3n）
5 0.25q^2-121p^2=(0.5q+11p)(0.5q-11p)
6 169x^2-4y^2=(13x+2y)(13x-2y)
7 9a^2p^2-b^2q^2=(3ap+bq)(3ap-bq)
8 49a^2-x^2y^2=(7a+xy)(7a-xy)
（m+n)^2-N^2=(m+n+N)(m+n-N)

49(a-b)^2-16(a+b)^2=[7(a-b)+4(a+b)][7(a-b)-4(a+b)]=(11a-3b)(3a-11b)

(2x+y)^2-(x+2y)^2=[(2x+y)+(x+2y)][(2x+y)-(x+2y)]=(3x+3y)(x-y)=3(x+y)(x-y)

(x^2+y^2)^2-x^2 y^2=(x²+y²+xy)(x²+y²-xy)

3ax^2-3ay^4=3a(x²-y^4)=3a(x+y²)(x-y²)

p^4-1=(p²+1)(p²-1)=(p²+1)(p+1)(p-1)

Answer 5

1.(a-9)(a+9)
2.(6-x)(6+x)
3.(1+4b)(1-4b)
4..(m+3n)(m-3n)
5..(0.5q+11p)(0.5q-11p)
6.(13x+2y)(13x-2y)
7.(3ap+bq)(3ap-bq)
8好像题目错了哦