Question

Determinați elementele B={y€N|9<√y <10}.

Answer 1

Răspuns:

$9 < \sqrt{y} < 10$

$\sqrt{81} < \sqrt{y} < \sqrt{100}$

B = { 82, 83, 84, ... 99}

Answer 2

Răspuns:

...

Explicație pas cu pas:

$B = \{y \in \mathbb{N} | 9 < \sqrt{y} < 10 \} \\ \\ \implies 9 < \sqrt{y} < 10 \implies \: 81 < y < 100 \\ \\ \implies \: y \in \{82, 83,...,98,99 \} \\ \\ \implies \: B = \{82, 83,...,98,99 \}$