Question

Det. perechile(x,y) ,xE Z, yE Z,stiind ca Ix-1I=2 si Ix-yI I....I -inseamna modul

Answer 1

|x-1|=2 (ai 2 cazuri cand x-1=2 si cand x-1=-2) => x={-1,3}
|x-y|<=1 (ai 4 cazuri, 2 cand x e -1 (-1-y<=1 si -1-y<=-1) si 2 cand x e 3 (3-y<=1 si 3-y<=-1). Intersectezi toate rezultatele si cred ca iti da y={1,2,3,4}.
Ai 8 perechi.