根号下x+y-3+绝对值xxy+x+y-2=0 x+y-3=0 xy+x+y-2=0 x+y=-3 x+y-3=xy+x+y-2
问题描述:
根号下x+y-3+绝对值xxy+x+y-2=0 x+y-3=0 xy+x+y-2=0 x+y=-3 x+y-3=xy+x+y-2
根号下x+y-3+绝对值xxy+x+y-2=0 x+y-3=0 xy+x+y-2=0 x+y=-3 x+y-3=xy+x+y-2 求x:y+y:x= y分之x+x分之y=
答
√(x+y-3)+|xy+x+y-2|=0 => x+y-3=0,xy+x+y-2=0 => x+y=3,xy=-1
x/y+y/x=(x^2+y^2)/(xy)=[(x+y)^2-2xy]/(xy)=[3^2-2*(-1)]/(-1)=-11