Question

Ex 21 si 22 pls Dau coroana!!!

Answer 1

Explicație pas cu pas:

21. a)

$9 - n \geqslant 0 \implies n \leqslant 9 \\ \iff n \in \Big(-\infty ;9 \Big]$

b)

$2n - 6 \geqslant 0 \iff 2n \geqslant 6 \\ \implies n \geqslant 3 \iff n \in \Big[3 ; +\infty \Big)$

c)

$10 - n \geqslant 0 \implies n \leqslant 10 \\ \iff n \in \Big(-\infty ;10 \Big]$

d)

$13 - 3n \geqslant 0 \iff 3n \leqslant 13 \\ \implies n \leqslant \dfrac{13}{3} \iff n \in \Big(-\infty ;\dfrac{13}{3} \Big]$