Question

am nevoie de acest exercițiu ​

Answer 1

Răspuns:

Explicație pas cu pas:

Answer 2

Răspuns:

a) $\sqrt{5+4} + \sqrt{2*5+6} = \sqrt{9} +\sqrt{16} = 3+4$ = 7

b)

$\sqrt{n+4}< 2\sqrt{7} \leq \sqrt{2n+6}$ (Facem inegalitatile pe rand)

1.

$\sqrt{n+4}<2\sqrt{7} \\ (\sqrt{n+4})^2<(2\sqrt{7})^2\\n+4 < 28\\n < 24$

2.

$2\sqrt{7} \leq \sqrt{2n+6} \\(2\sqrt{7})^2 \leq (\sqrt{2n+6})^2 \\28 \leq 2n+6\\22\leq 2n\\11\leq n$

=> n apartine 11, 12, 13, 14,...,23

Explicație pas cu pas: