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给我出十道用分组分解法解的分解因式

题目详情
给我出十道用分组分解法解的分解因式
▼优质解答
答案和解析
1)a^2-b^2-a-b
=(a^2-b^2)-(a+b)
=(a+b)(a-b)-(a+b)
=(a+b)(a-b-1)
2)a^2-2ab+b^2-1
=(a^2-2ab+b^2)-1
=(a-b)^2-1
=(a-b+1)(a-b-1)(x+2)
3..(x-2)-4y(x-y)
=x²-4-4xy+4y²
=(x²-4xy+4y²)-4
=(x-2y)²-2²
=(x-2y+2)(x-2y-2)c²+a²-b²+2ac
=(a+c)²-b²
=(a+c-b)(a+c+b)
4..2a²-2+2b²-4ab
=2(a²-2ab+b²)-2
=2[(a-b)²-1]
=2(a-b-1)(a-b+1)
5..x^3+x²y-x²z-xyz
=x²(x+y)-xz(x+y)
=(x²-xz)(x+y)
=x(x-z)(x+y)
6.=(4a^2+4a+1)-b(4a^2-1) *
=(2a+1)^2-b(2a+1)(2a-1)
=(2a+1)[2a+1-b(2a-1)]
=(2a+1)(-2ab+2a+b+1)
=-(2a+1)(2ab-2a-b-1)
7.=(4x^4+4x^2+1)-4x^2 *
=(2x^2+1)^2-(2x)^2
=(2x^2+2x+1)(2x^2-2x+1)
8.=(x^4+2x^2+1)-9x^2 *
=(x^2+1)^2-(3x)^2
=(x^2+3x+1)(x^2-3x+1)
9.=x^2y^2-x^2-y^2-4xy+1
=(x^2y^2-2xy+1)-(x^2+2xy+y^2) *
=(xy-1)^2-(x+y)^2
=(xy+x+y-1)(xy-x-y-1)
10.=x^2-2x-y^2+1
=(x^2-2x+1)-y^2 *
=(x-1)^2-y^2
=(x+y-1)(x-y-1)
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