Question

A={x aparține Z | modul de x mai mic sau egal 3}
A=?

Answer 1

$|x| = | - x| = x$

$A=\left \{ x\:\in\:\mathbb{Z} \:|\:|x|\leq 3\right \}$

$|0| = 0 \leq3$

$| - 1| = |1| = 1 \leq 3$

$| - 2| = |2| = 2 \leq 3$

$| - 3| = |3| = 3 \leq 3$

$= > x \: \in \: \left \{ 0,\pm1,\pm2,\pm3 \right \}$

$= > A =\left \{ 0,\pm1,\pm2,\pm3 \right \}$