x + y + xy = 2
=> (x + xy) + (y + 1) = 3
=> (y + 1)(x + 1) = 3
=> [(x + 1),(y + 1)] = (1,3;3,1;-1,-3;-3,-1)
=> (x,y) = (0,2;0,2;-2,-4;-4,-2)
a)x + y + xy = 2
=> (x + xy) + (y + 1) = 3
=> (y + 1)(x + 1) = 3
=> [(x + 1),(y + 1)] = (1,3;3,1;-1,-3;-3,-1)
=> (x,y) = (0,2;0,2;-2,-4;-4,-2)
ai lam cau b gip minh voi
a)x+y+xy=2
=>(x+xy)+(y+1)=3
=>(y+1)(x+1)=3
=>[(x+1).(y+1)]=(1,3;3;1;-1;-3;-1)
=>(xy)=(0,2 ; 0,2; -2,-4 ; -4,-2)