打了好久,你一分都没有给,好吝啬哦,开个玩笑.
1、平方展开=a^2x^2+b^2y^2+b^2x^2+a^2y^2
=(x^2+y^2)(a^2+b^2)
2、原式=x^4-2x^3+x^2-4x^2+4x+4= x^4-2x^3-3x^2+4x+4= (x^4-2x^3)-(3x^2-4x-4)=x^3(x-2)-(x-2)( 3x+2)=(x-2)( x^3-3x-2)
3、原式=(2（x+y）-3(x-y))( 2（x+y）+3(x-y))=(5x-y)(y-x)
4、原式=(a+b)(a-b)+4(b-1)
=a^2-b^2+4b-4
=a^2-(b^2-4b+4)
=a^2-(b-2)^2
=(a+b-2)(a-b+2)
5、原式=x^2+4xy+4y^2-2x-4y-3
=(x+2y)^2-2(x+2y)-3
=(x+2y-3)(x+2y+1)
6、原式=(x+1)(x+4)*(x+2)(x+3)+1
=(x^2+5x+4)(x^2+5x+6)+1
=(x^2+5x+4)[(x^2+5x+4)+2]+1
=(x^+5x+4)^2+2(x^2+5x+4)+1
=[(x^2+5x+4)+1]^2
=(x^2+5x+5)^2
7、原式=(3x-5)(x-2)