Question

alguém me ajuda passo a passo como resolve ?

Answer 1

Olá!

a)

$\sqrt{8}\sqrt{6}\\\\=2\sqrt{2}\sqrt{6}\\\\=2\sqrt{2}\sqrt{2\cdot \:3}\\\\=2\sqrt{2}\sqrt{2}\sqrt{3}\\\\=2\cdot \:2\sqrt{3}\\\\=4\sqrt{3}$

b)

$\sqrt{2}\sqrt{27}\\\\=\sqrt{2}\cdot \:3\sqrt{3}\\\\=3\sqrt{2\cdot \:3}\\\\=3\sqrt{6}$

c)

$\sqrt{42}\sqrt{28}\\\\=\sqrt{42}\cdot \:2\sqrt{7}\\\\=\sqrt{7\cdot \:6}\cdot \:2\sqrt{7}\\\\=\sqrt{7}\sqrt{6}\cdot \:2\sqrt{7}\\\\=2\cdot \:7\sqrt{6}\\\\=14\sqrt{6}$

d)

$2\sqrt{10}\cdot \:5\sqrt{30}\\\\=2\sqrt{2\cdot \:5}\cdot \:5\sqrt{30}\\\\=2\sqrt{2}\sqrt{5}\cdot \:5\sqrt{30}\\\\=2\sqrt{2}\sqrt{5}\cdot \:5\sqrt{2\cdot \:5\cdot \:3}\\\\=2\sqrt{2}\sqrt{5}\cdot \:5\sqrt{2}\sqrt{5}\sqrt{3}\\\\=2\cdot \:5\cdot \:2\sqrt{5}\sqrt{5}\sqrt{3}\\\\=2\cdot \:5\cdot \:2\cdot \:5\sqrt{3}\\\\=100\sqrt{3}$

e)

$\sqrt{8}\sqrt{12}\cdot \:10\sqrt{3}\\\\=\sqrt{8}\sqrt{36}\cdot \:10\\\\=\sqrt{8}\cdot \:6\cdot \:10\\\\=\sqrt{2^3}\cdot \:6\cdot \:10\\\\=\sqrt{2^2\cdot \:2}\cdot \:6\cdot \:10\\\\=2\sqrt{2}\cdot \:6\cdot \:10\\\\=120\sqrt{2}$

f)

$6\sqrt{7}\cdot \:5\sqrt{2}\cdot \:8\sqrt{21}\\\\=6\sqrt{7}\cdot \:5\sqrt{2}\cdot \:8\sqrt{7\cdot \:3}\\\\=6\sqrt{7}\cdot \:5\sqrt{2}\cdot \:8\sqrt{7}\sqrt{3}\\\\=1680\sqrt{2}\sqrt{3}\\\\=1680\sqrt{2\cdot \:3}\\\\=1680\sqrt{6}$

Espero ter ajudado, tenha boas aulas!