因式分解3x(4x-5y)-6y(5y-4x)

来源：百度知道 编辑：UC知道 时间：2024/06/04 01:20:04
3x(4x-5y)-6y(5y-4x) 81-3x^3
2(x+1)^2-4(x+1)
(x-3)(3x-2)-7(x-3)
a^3+64
(3m+2n)^2-(m-n)^2
(2a+b)(2a-3b)+a(2a+b)
m^2+5n-mn-5m
这些我不玩 大虾帮帮忙啊

1.
3x(4x-5y)-6y(5y-4x)
=3x(4x-5y)+6y(4x-5y)
=(4x-5y)(3x+6y)
=3(4x-5y)(x+2y)

2.
81-3x^3
=-(3x^3-81)
=-3(x^3-27)
=-3(x-3)(x^2+9+3x)

3.
2(x+1)^2-4(x+1)
=(x+1)[2(x+1)-4]
=2(x+1)[(x+1)-2]
=2(x+1)(x+1-2)
=2(x+1)(x-1)

4.
(x-3)(3x-2)-7(x-3)
=(x-3)[(3x-2)-7]
=(x-3)(3x-2-7)
=(x-3)(3x-9)
=3(x-3)(x-3)
=3(x-3)^2

5.
a^3+64=(a+4)(a^2+16-4a)

6.
(3m+2n)^2-(m-n)^2
=[(3m+2n)-(m-n)][(3m+2n)+(m-n)]
=(3m+2n-m+n)(3m+2n+m-n)
=(2m+3n)(4m+n)

7.
(2a+b)(2a-3b)+a(2a+b)
=(2a+b)[(2a-3b)+a]
=(2a+b)(2a-3b+a)
=(2a+b)(3a-3b)
=3(2a+b)(a-b)

8.
m^2+5n-mn-5m
=(m^2-5m)+(5n-mn)
=m(m-5)+n(5-m)
=m(m-5)-n(m-5)
=(m-5)(m-n)

3x(4x-5y)-6y(5y-4x)=-3x(5y-4x)-6y(5y-4x)=-(5y-4x)(3x+6y)
81-3x^3=(9+3x)(9-3x)
2(x+1)^2-4(x+1)=4(x+1)(x+1-1)=4x(x+1)
(x-3)(3x-2)-