Question

Ex 14 pls dau coroana!!!

Answer 1

Răspuns:

14)

Explicație pas cu pas:

a)

$|x| = 1 \implies \\ x = - 1 ; \ \ x = 1$

A = {-1; 1}

b)

$\sqrt{2} < x < \sqrt{10} \\ 1 < \sqrt{2} < 2 \\ 3 < \sqrt{10} < 4 \\ \iff 1 < x < 4$

B = {2; 3}

c)

$|x + 1| = 3 \\ x + 1 = - 3 \implies x = - 4 ∉ \mathbb{N}\\ x + 1 = 3 \implies x = 2$

C = {2}

d)

$|x + 1| = \sqrt{2} \\ x + 1 = - \sqrt{2} \implies x = - \sqrt{2} - 1\\ x + 1 = \sqrt{2} \implies x = \sqrt{2} - 1$

D = {-√2 - 1; √2 - 1}