已知:3|x+1|+2(y-1)^2=0,求多项式(x^2+4xy-2y^2)-(x^2+y)-2(y^2+xy)-1/2(x-8y^2)的值
问题描述:
已知:3|x+1|+2(y-1)^2=0,求多项式(x^2+4xy-2y^2)-(x^2+y)-2(y^2+xy)-1/2(x-8y^2)的值
答
3|x+1|+2(y-1)^2=0x+1=0y-1=0x=-1y=1(x^2+4xy-2y^2)-(x^2+y)-2(y^2+xy)-1/2(x-8y^2)=x^2+4xy-2y^2-x^2-y-2y^2-2xy-1/2x+4y^2=2xy-1/2x=2*(-1)*1-1/2*(-1)=-2+1/2=-3/2