几道不知道是初中还是高中的数学题 急要答案分解因式 27-x^3=x^3-6x^2+12x-8=27-x^6=125m^3+8n^3=a^3+3ab^2+3a^2b+b^3-c^2=(m+n)^2-4(m+n-1)=x^4y^2-6x^2-8=x^2-3xy+2y^2=4x^2y^2-5x^2y^2-9y^2=(a-b)x^2+2ax+a+b=(a^2-a)x^2-(ab+2b)x-6b^2=

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几道不知道是初中还是高中的数学题 急要答案分解因式 27-x^3=x^3-6x^2+12x-8=27-x^6=125m^3+8n^3=a^3+3ab^2+3a^2b+b^3-c^2=(m+n)^2-4(m+n-1)=x^4y^2-6x^2-8=x^2-3xy+2y^2=4x^2y^2-5x^2y^2-9y^2=(a-b)x^2+2ax+a+b=(a^2-a)x^2-(ab+2b)x-6b^2=
几道不知道是初中还是高中的数学题 急要答案
分解因式 27-x^3=
x^3-6x^2+12x-8=
27-x^6=
125m^3+8n^3=
a^3+3ab^2+3a^2b+b^3-c^2=
(m+n)^2-4(m+n-1)=
x^4y^2-6x^2-8=
x^2-3xy+2y^2=
4x^2y^2-5x^2y^2-9y^2=
(a-b)x^2+2ax+a+b=
(a^2-a)x^2-(ab+2b)x-6b^2=

几道不知道是初中还是高中的数学题 急要答案分解因式 27-x^3=x^3-6x^2+12x-8=27-x^6=125m^3+8n^3=a^3+3ab^2+3a^2b+b^3-c^2=(m+n)^2-4(m+n-1)=x^4y^2-6x^2-8=x^2-3xy+2y^2=4x^2y^2-5x^2y^2-9y^2=(a-b)x^2+2ax+a+b=(a^2-a)x^2-(ab+2b)x-6b^2=
解题:
1.27-x^3 =3^3-x^3=(3-x)(9+3x+x^2) [立方差公式]
2.x^3-6x^2+12x-8=(X^3-8)-(6X^2-12X)=(X^3-2^3)-6X(X-2)=(X-2)(X^2+2X+4)-6x(x-2)=(x-2)(x^2-4x+4)=(x-2)^3 [拆分法]
3.27-x^6=3^3-(x^2)^3=(3-x^2)(9+3x^2+x^4)=(3-x^2){(x^2+3)^2-3x^2}=(3-x^2)(x^2+3+√3x)(x^2+3-√3x) [一次立方差公式、一次平方差公式]
4.125m^3+8n^3=(5m)^3+(2n)^3=(5m+2n)(25m^2+10mn+4n^2) [立方和公式]
5.a^3+3ab^2+3a^2b+b^3-c^2=(a+b)^3-c^2 [计题目抄写有误]
6.(m+n)^2-4(m+n-1)=(m+n)^2-4(m+n)+4=(m+n-2)^2 [完全平方和公式]
7.x^4y^2-6x^2-8 [估计题目抄写有误]
8.x^2-3xy+2y^2=(x-2y)(x-y) [十字相乘法]
9.4x^2y^2-5x^2y^2-9y^2 [估计题目抄写有误]
10.(a-b)x^2+2ax+a+b={(a-b)x+a+b}(x+1) [十字相乘法]
11.(a^2-a)x^2-(ab+2b)x-6b^2=a(a-1)x^2-(ab+2b)x-2b*3b=(ax+2b){(a-1)x-3b} [十字相乘法]

1:(3-x)*(9+3x+x^2)
2:x(x-3)^2+3x-8
3:(3-x^2)(9+3x^2+x^4)
4:(6m+2n)(25m^2-10mn+4n^2)
5:(a+b)^3-c^2
6:(m+n)^2-4m-4n+4
=(m+n)^2-4(m+n)+4
=(m+n-2)^2
7:x^2(x^2y^2-6)-8<...

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1:(3-x)*(9+3x+x^2)
2:x(x-3)^2+3x-8
3:(3-x^2)(9+3x^2+x^4)
4:(6m+2n)(25m^2-10mn+4n^2)
5:(a+b)^3-c^2
6:(m+n)^2-4m-4n+4
=(m+n)^2-4(m+n)+4
=(m+n-2)^2
7:x^2(x^2y^2-6)-8
8:(x-y)(x-2y)
9:-y^2(x+3)(x-3)
10:ax^2-bx^2+2ax+a+b
ax^2+2ax+a-bx^2+b
(ax+a)(x+1)-b(1-x^2)
(ax+a)(x+1)+b(x^2-1)
(ax+a)(x+1)+b(x+1)(x-1)
(x+1)(a(x+1)+b(x-1))
11:

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