因式分解的题目。快点！

来源：百度知道 编辑：UC知道 时间：2024/05/11 21:44:40
①4(a+b)²-9a+9b
②x²/25-y²/16
③-3x+6x²-3X的³
④0.1a的四次方+0.8a²+1.6
⑤[（3x-7)²-(x+5)²]÷（4x-24)

好多显示不出来得…这可以我的强项的…看不到…

①
4(a+b)^2-9a-9b
=4(a+b)^2-(9a+9b)
=4(a+b)^2-9(a+b)
=(a+b)[4(a+b)-9]
=(a+b)(4a+4b-9)

②
x^2/25-y^2/16=(x/5-y/4)(x/5+y/4)

③
-3x+6x^2-3x^3
=-(3x-6x^2+3x^3)
=-x(3-6x+3x^2)
=-3x(1-2x+x^2)
=-3x(x-1)^2

④
0.1a^4+0.8a^2+1.6

⑤
[(3x-7)^2-(x+5)^2]÷(4x-24)
=[(3x-7)-(x+5)][(3x-7)+(x+5)]÷(4x-24)
=[(3x-7-x-5)(3x-7+x+5)]÷(4x-24)
=[(2x-12)(4x-2)]÷(4x-24)
=[2(x-6)(4x-2)]÷(4x-24)
=[4(x-6)(2x-1)]÷(4x-24)
=[4(x-6)(2x-1)]÷4(x-6)
=2x-1