Question

Elementele multimi A=(x€N*|2x+3<9 Sunt:

Answer 1

x e N = 2x+3<9/-3
=2x<6/:3
x={1,2}

Answer 2

$A = \left\{x\:\in\:\mathbb{{N}^{*}} \: | \: 2x + 3 < 9 \right\}$

$2x + 3 < 9$

$2x < 9 - 3$

$2x < 6 \: | \div 2$

$x < 3 = ( - \infty ,3)$

$x \: \in \: \mathbb{{N}}^{*} = > x \: \in \: \left\{1,2\right\}$

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