【解】x+xy+y=2+3√2 x^2+y^2=6 所以2x+2xy+2y+x^2+y^2=4+6√2 +6=10+6√2 (x+y)^2+2(x+y)=10+6√2 (x+y+1)^2=11+6√2=(3+√2)^2所以 |x+y+1 | =3+√2