Question

preciso das contas, os resultados são:
a)7√5+5
b)3√5+5√3
c)4√2-4√3​

Answer 1

Resposta:

a)$\sqrt{5}\left(7+\sqrt{5}\right) = \sqrt{5}\cdot \:7+\sqrt{5}\sqrt{5} = 7\sqrt{5}+5$

b) $\sqrt{15}\left(\sqrt{3}+\sqrt{5}\right) = \sqrt{15}\sqrt{3}+\sqrt{15}\sqrt{5} = \sqrt{45} + \sqrt{75} = =\sqrt{3^2\cdot\:5} + \sqrt{3\cdot \:5^2} = 3\sqrt{5} + 5\sqrt{3}$

c) $\sqrt{8}\left(2-\sqrt{6}\right) =\sqrt{2^3}\left(2-\sqrt{6}\right) = 2\sqrt{2}\left(2-\sqrt{6}\right) = 2\sqrt{2}\cdot \:2 - 2\sqrt{2}\sqrt{6} = 4\sqrt{2}-4\sqrt{3}$