Question

determinați mulțumea A unde A = { x|x e N si x | 18 si 2x + 3 < 15} va rog frumooos dau 10 puncte

Answer 1

$A=\left\{x\:|\:x\:\in\:\mathbb{N}\:si\:x|18\: \: si \: \: 2x+3 \:<\:15\right\}$

$2x + 3 < 15$

$2x < 15 - 3$

$2x < 12 \: | \div 2$

$x < 6$

$x \: \in \: \mathbb{N} = > \left\{0,1,2,3,4,5\right\}$

$dar \: x |18 = > x \: \in \: \left\{1,2,3\right\}$

$A=\left\{1,2,3\right\}$