活着真好的句子:因式分解

xy(xy+1)+(xy+3)-2(x+y+0.5)-(x+y-1)^2
=xy(xy+1)+(xy+1)+2-[2(x+y)+1]-[(x+y)^2-2(x+y)+1]
=(xy+1)^2-(x+y)^2
=(xy+1+x+y)(xy+1-x-y)
=[x(y+1)+(y+1)][x(y-1)-(y-1)]
=(x+1)(y+1)(x-1)(y-1)

(x^2+3x+4)^2+(x^2+3x+4)-6
=(x^2+3x+4+3)(x^2+3x+4-2)
=(x^2+3x+7)(x^2+3x+2)
=(x^2+3x+7)(x+1)(x+2)

1.全打开
原式=x^2*y^2+xy+xy+3-2x-2y-1-(x+y-1)^2
=x^2*y^2+2xy+1-2x-2y+1-(x+y-1)^2
=(xy+1)^2-2(x+y-1)-(x+y-1)^2
=(xy+1)^2-(x+y-1+2)^2
=(xy+1-x-y-1)(xy+1+x+y+1)
=(xy-x-y)(xy+x+y+2)
2.
原式=(x^2+3x+4)^2+x^2+3x+4-6
=(x^2+3x+4)(x^2+3x+5)-6
然后就不会了.................-_-!!

1.原式=x^2*y^2+xy+xy+3-2x-2y-1-(x+y-1)^2
=x^2*y^2+2xy+1-2x-2y+1-(x+y-1)^2
=(xy+1)^2-2(x+y-1)-(x+y-1)^2
=(xy+1)^2-(x+y-1+2)^2
=(xy+1-x-y-1)(xy+1+x+y+1)
=(xy-x-y)(xy+x+y+2)
2.X^2+3X+4为y，则原式=y^2+y-6=(y+3)(y-2)
=(x^2+3x+7)(x^2+3x+2)
=(x^2+3x+7)(x+1)(x+2)

2 2 2 2
X Y +XY+XY+3-2X-2Y-1-(X +Y +1+2XY-2X-2Y)
2 2 2 2
=X Y +1-X -Y
2 2 2
=X (Y -1)-(Y -1)
2 2
=(Y -1)(X -1)

2 2 2
(X +3X+4) +(X +3X+4)-6
4 2 3 2 2
=X +9X +16+6X +8X +24X+X +3X+4-6
4 3 2
=X +6X +18X +27X+14
3
=X (X+6)+18X(X+6)-108X+27X+14
3
=X (X+6)+18X(X+6)-81X+14
3
=X (X+6)+18X(X+6)-81(X+6)+486+14
3
=(X+6)(X +18X-81)+500
3 2
{{{=(X+6)(X +2*9X-9 )+500}}}