1、4(2x^2-x+1)(x^2+3-2x)-(3x^2-3x+4)^22、xy(xy+1)+(xy+3)-2(x+y+1/2)-(x+y-1)^2第二道题如果答案是(x+1)(y+1)(xy+x+y-1)就不用要过程了.有答案保证+分
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![1、4(2x^2-x+1)(x^2+3-2x)-(3x^2-3x+4)^22、xy(xy+1)+(xy+3)-2(x+y+1/2)-(x+y-1)^2第二道题如果答案是(x+1)(y+1)(xy+x+y-1)就不用要过程了.有答案保证+分](/uploads/image/z/14730921-9-1.jpg?t=1%E3%80%814%282x%5E2-x%2B1%29%28x%5E2%2B3-2x%29-%283x%5E2-3x%2B4%29%5E22%E3%80%81xy%EF%BC%88xy%2B1%EF%BC%89%2B%28xy%2B3%29-2%28x%2By%2B1%2F2%29-%28x%2By-1%29%5E2%E7%AC%AC%E4%BA%8C%E9%81%93%E9%A2%98%E5%A6%82%E6%9E%9C%E7%AD%94%E6%A1%88%E6%98%AF%28x%2B1%EF%BC%89%EF%BC%88y%2B1%EF%BC%89%EF%BC%88xy%2Bx%2By-1%EF%BC%89%E5%B0%B1%E4%B8%8D%E7%94%A8%E8%A6%81%E8%BF%87%E7%A8%8B%E4%BA%86.%E6%9C%89%E7%AD%94%E6%A1%88%E4%BF%9D%E8%AF%81%2B%E5%88%86)
1、4(2x^2-x+1)(x^2+3-2x)-(3x^2-3x+4)^22、xy(xy+1)+(xy+3)-2(x+y+1/2)-(x+y-1)^2第二道题如果答案是(x+1)(y+1)(xy+x+y-1)就不用要过程了.有答案保证+分
1、4(2x^2-x+1)(x^2+3-2x)-(3x^2-3x+4)^2
2、xy(xy+1)+(xy+3)-2(x+y+1/2)-(x+y-1)^2
第二道题如果答案是(x+1)(y+1)(xy+x+y-1)就不用要过程了.
有答案保证+分
1、4(2x^2-x+1)(x^2+3-2x)-(3x^2-3x+4)^22、xy(xy+1)+(xy+3)-2(x+y+1/2)-(x+y-1)^2第二道题如果答案是(x+1)(y+1)(xy+x+y-1)就不用要过程了.有答案保证+分
1、4(2x^2-x+1)(x^2+3-2x)-(3x^2-3x+4)^2
=4(2x^2-x+1)(x^2-2x+3)-[(2x^2-x+1)+(x^2-2x+3)]^2
=4(2x^2-x+1)(x^2-2x+3)-(2x^2-x+1)^2-2(2x^2-x+1)(x^2-2x+3)-(x^2-2x+3)^2
=-(2x^2-x+1)^2+2(2x^2-x+1)(x^2-2x+3)-(x^2-2x+3)^2
=-[(2x^2-x+1)^2-2(2x^2-x+1)(x^2-2x+3)-(x^2-2x+3)^2]
=-[(2x^2-x+1)-(x^2-2x+3)^2]^2
=-(x^2+x-2)^2
=-(x-1)^2(x+2)^2
2、xy(xy+1)+(xy+3)-2(x+y+1/2)-(x+y-1)^2
=x^2y^2+xy+xy+3-2(x+y)-1-(x+y)^2+2(x+y)-1
=x^2y^2+2xy+1-(x+y)^2
=(xy+1)^2-(x+y)^2
=(xy+1+x+y)(xy+1-x-y)
=(x+1)(y+1)(x-1)(y-1)