已知(x+2)2+|y一1/3|=0,求2(xy一5xy2)一(2xy2一xy)

2022-06-06

答案：

(x+2)2+|y一1/3|=0,则x+2=0y-1/3=0则x=-2,y=1/3则2(xy一5xy2)一(2xy2一xy)=2xy-10xy^2-2xy^2+xy=3xy-12xy^2=3xy(1-4y)=-2*(1-4/3)=2/3

分解因式()x()3()y()-()2()x()2()y()2()+()xy()3()正确的是A.()xy()(()x()+()y())()2()B.()xy()(()x()2()﹣()2()xy()+()y()2())()C.()xy()(()x()2()+2()xy()﹣()y()2())()D.()xy()(()x()﹣()y())()2
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