Question

2-A Expressao com radicais √8-√18+2√2 é igual a : (a)√2    (b)√12    (c)-√8   (d)-3√2

Answer 1

$\sqrt{8}- \sqrt{18}+2 \sqrt{2} \\ \\ \sqrt{8}= \sqrt{4}* \sqrt{2}=2 \sqrt{2} \\ \\ \sqrt{18}= \sqrt{9}* \sqrt{2}=3 \sqrt{2} \\ \\ 2 \sqrt{2}- 3\sqrt{2}+2 \sqrt{2} \\ \sqrt{2}(2-3+2)= \sqrt{2}$

R:A

Answer 2

Raiz de 8 = 2 raiz de 2
Raiz de 18 = 3 raiz de 2
Logo,
$2 \sqrt{2}-3 \sqrt{2}+2 \sqrt{2}= 4 \sqrt{2}-3 \sqrt{2}= \sqrt{2}$