初二数学计算题!谢谢!EASY!急1.x(x-1)(x-2)-62.1-xy(1-xy)-x^3y^33.x^2+4xy+4y^2-2x-4y+1谢谢要过程!要过程!要过程!要过程!要过程!要过程!要过程!
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初二数学计算题!谢谢!EASY!急1.x(x-1)(x-2)-62.1-xy(1-xy)-x^3y^33.x^2+4xy+4y^2-2x-4y+1谢谢要过程!要过程!要过程!要过程!要过程!要过程!要过程!
初二数学计算题!谢谢!EASY!急
1.x(x-1)(x-2)-6
2.1-xy(1-xy)-x^3y^3
3.x^2+4xy+4y^2-2x-4y+1
谢谢
要过程!
要过程!
要过程!
要过程!
要过程!
要过程!
要过程!
初二数学计算题!谢谢!EASY!急1.x(x-1)(x-2)-62.1-xy(1-xy)-x^3y^33.x^2+4xy+4y^2-2x-4y+1谢谢要过程!要过程!要过程!要过程!要过程!要过程!要过程!
1.x(x-1)(x-2)-6
=x[x^2-3x+2]-6
=x^3-3x^2+2x-6
=x^2(x-3)+2(x-3)
=[x-3][x^2+2]
2.1-xy(1-xy)-x^3y^3
=[1-xy][1+xy+x^2y^2]-xy[1-xy]
=[1-xy][1+xy+x^2y^2-xy]
=[1-xy][1+x^2y^2]
3.x^2+4xy+4y^2-2x-4y+1
=[x+2y]^2-2[x+2y]+1
=[x+2y-1]^2
1.x(x-1)(x-2)-6
=x(x^2-3x+2)-6
=x^3-3x^2+2x-6
=x^2(x-3)+2(x-3)
=(x-3)(x^2+2)
2.1-xy(1-xy)-x^3y^3
=1-xy+x^2y^2-x^3y^3
=(1-xy)+x^2y^2(1-xy)
=(1-xy)(1+x^2y^2)
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1.x(x-1)(x-2)-6
=x(x^2-3x+2)-6
=x^3-3x^2+2x-6
=x^2(x-3)+2(x-3)
=(x-3)(x^2+2)
2.1-xy(1-xy)-x^3y^3
=1-xy+x^2y^2-x^3y^3
=(1-xy)+x^2y^2(1-xy)
=(1-xy)(1+x^2y^2)
3.x^2+4xy+4y^2-2x-4y+1
=(x^2+4xy+4y^2)-(2x+4y)+1
=[x^2+4xy+(2y)^2]-2(x+2y)+1
=(x+2y)^2-2(x+2y)+1
=[(x+2y)-1]^2
=(x+2y-1)^2
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