Question

Elementele multimi A={XeZ / x+5 supra x+2 eZ} sunt

Answer 1

x+2 | x+5 (divide)
x+2 | x+2 (inmultim cu -1

x+2 | x+5
x+2 | -x-2 ( adunam cele doua relatii )

x+2 | 3 ( x s a redus )

x+2 € { -3,-1,1,3 }

x+2=-3 => x=-5
x+2=-1 => x=-3
x+2=1 => x=-1
x+2=3 => x=1.