Question

Ex 4, va rog....E urgent !!!!

Answer 1

2x - 1 | 3

2x - 1 apartine divizorilor intregi ai lui 3

2x - 1 apartine {-3; -1; 1; 3}

2x apartine {-2; 0; 2; 4}

x apartine {-1; 0; 1; 2}

A = {-1; 0; 1; 2}

card A = 4