初二下学期分解因式[数学]1.a(x-y)-b(y-x)+c(x-y)2.x(m+n)-y(n+m)+(m+n)3.(x+y)²-16(x-y)²4.a²(a-b)²-b²(a+b)²5.(x+y+z)²-(x-y-z)²6.x²y-2xy²+y³7.16-(2a+3b)²8.(a²+4)²-16a²9.

初二下学期分解因式[数学]1.a(x-y)-b(y-x)+c(x-y)2.x(m+n)-y(n+m)+(m+n)3.(x+y)²-16(x-y)²4.a²(a-b)²-b²(a+b)²5.(x+y+z)²-(x-y-z)²6.x²y-2xy²+y³7.16-(2a+3b)²8.(a²+4)²-16a²9.
初二下学期分解因式[数学]
1.a(x-y)-b(y-x)+c(x-y)
2.x(m+n)-y(n+m)+(m+n)
3.(x+y)²-16(x-y)²
4.a²(a-b)²-b²(a+b)²
5.(x+y+z)²-(x-y-z)²
6.x²y-2xy²+y³
7.16-(2a+3b)²
8.(a²+4)²-16a²
9.9+6(a+b)+(a+b)²
10.(x+1)(x+2)+1/4
11.(a+b/2)²-(a-b/2)²

初二下学期分解因式[数学]1.a(x-y)-b(y-x)+c(x-y)2.x(m+n)-y(n+m)+(m+n)3.(x+y)²-16(x-y)²4.a²(a-b)²-b²(a+b)²5.(x+y+z)²-(x-y-z)²6.x²y-2xy²+y³7.16-(2a+3b)²8.(a²+4)²-16a²9.
解.
1.原式=a(x-y)＋b(x－y)+c(x-y)
=（a+b+c）（x-y）
2.原式=（x-y+1)（m+n）
3.原式=｛（x+y)＋4(x-y)｝｛（x+y)－4(x-y)｝
=（5x-3y）（5y-3x）
4.原式=｛a(a-b)＋b(a+b)｝｛a(a-b)-b(a+b)｝
=（a²＋b²）（a²－2ab-b²）
5.原式=｛(x+y+z)＋(x-y-z)｝｛(x+y+z)－(x-y-z)｝
=2x（2y＋2z）
6.原式=y（x-y）²
7.原式=（4-2a-3b）（4＋2a+3b）
8.原式=（a²＋4＋4a）（a²＋4-4a）
=（a+2）²（a-2）
9.原式=（3+a+b）²
10.原式=(x+1)[(x+1)+1]+(1/2)²
=(x+1)^2+(x+1)+(1/2)²
=(x+1+1/2)(x+1+1/2)
=(x+3/2)(x+3/2)
11.原式=（a+b/2+a-b/2）（a+b/2-a+b/2）
=2ab

（1）原式=a(x-y)+b(x-y)+c(x-y)
=(a+b+c)(x-y)
(2) 原式=(m+n)(x-y+1)
(3) 原式=(x+y)²-（4x-4y）²
=(x+y+4x-4y)(x+y-4x+4y)
=(5x-3y)(5y-3...

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（1）原式=a(x-y)+b(x-y)+c(x-y)
=(a+b+c)(x-y)
(2) 原式=(m+n)(x-y+1)
(3) 原式=(x+y)²-（4x-4y）²
=(x+y+4x-4y)(x+y-4x+4y)
=(5x-3y)(5y-3x)
(4) 原式=(a²-ab)²-(ab+b²)²
=(a²-ab+ab+b²)(a²-ab-ab-b²)
=(a²+b²)(a²-2ab-b²)
(5) 原式=(x+y+z+x-y-z)(x+y+z-x+y+z)
=2x×2(y+z)
=2(x+y+z)
(6) 原式=y(x²-2xy+y²)
=y(x-y)²
(7) 原式=4²-(2a+3b)²
=(4+2a+3b)(4-2a-3b)
(8) 原式=(a²+4)²-(4a)²
=(a²+4+4a)(a²+4-4a)
=(a+2)²(a-2)²
(9) 原式=3²+2×3（a+b)+(a+b)²
=(3+a+b)²
(10)原式=x²+3x+9/4
=x²+3x+(3/2)²
=[x+(3/2)]²
(11)原式=[(a+b+a-b)/2][(a+b-a+b)/2]
=ab

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