若x²+y²+4x-10y+29=0,则x²y+xy²=

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因为x2+y2+4x-10y+29=0，所以x^2+4x+4+y^2-10y+25=0，即(x+2)^2+(y-5)^2=0,解得x=-2,y=5,所以x2y+xy2=xy(x+y)=-10×3=-30...

千问 | 2012-3-13 21:40:30 | 显示全部楼层

x2+y2+4x-10y+29=0x2+4x+4+y2-10y+25=0(x+2)2+(y-5)2=0(x+2)2=0,(y-5)2=0x=-2y=5x2y+xy2=xy(x+y)=-2*5*(-2+5)=-10*3=-30...

千问 | 2012-3-13 21:40:30 | 显示全部楼层

x2+y2+4x-10y+29=0x2+4x+4+y2-10y+25=0(x+2)2+(y-5)2=0x+2=0x=-2y-5=0y=5x2y+xy2=xy(x+y)=-2x5(-2+5)=-10x3=-30...

千问 | 2012-3-13 21:40:30 | 显示全部楼层

有条件推出（x+2）2+（y-5）2=0，那么x=-2，y=5，推出结果为-30...

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