xy-x^2-2у+2х при х =2 2/3,у=3 2/3 поже на контрольную.

Xy-x^2-2у+2х при х =2 2/3,у=3 2/3х =2 2/3=8/3,у=3 2/3=11/3(11/3)(8/3)-(8/3)²-2(11/3)+2(8/3)=88/9-64/9-66/9+48/9=(88-64-66+48)/9=6/9==2/3