Question

Va rog ajutati ma la ex 3

Answer 1

Răspuns:

Explicație pas cu pas:

a)

$x=(\frac{8}{\sqrt{18}}+\frac{6}{\sqrt{2}})*\frac{\sqrt{2}}{13}=(\frac{8}{\sqrt{2}*\sqrt{9}}+\frac{6}{\sqrt{2}})*\frac{\sqrt{2}}{13}=(\frac{8}{3\sqrt{2}}+\frac{6}{\sqrt{2}})*\frac{\sqrt{2}}{13}=\frac{8+3*6}{3\sqrt{2}}*\frac{\sqrt{2}}{13}= \frac{26\sqrt{2}}{3*13*\sqrt{2}}=\frac{2}{3}$

b)

$y=(\frac{1}{\sqrt{3}}-\frac{5}{\sqrt{147}}):\frac{\sqrt{3}}{14}=(\frac{1}{\sqrt{3}}-\frac{5}{\sqrt{3}*\sqrt{49}})*\frac{14}{\sqrt{3}}=(\frac{1}{\sqrt{3}}-\frac{5}{7\sqrt{3}})*\frac{14}{\sqrt{3}}=\frac{7-5}{7\sqrt{3}}*\frac{14}{\sqrt{3}}=\frac{2*14}{7*\sqrt{3}*\sqrt{3}}=\frac{28}{21}=\frac{4}{3}$

$x+y=\frac{2}{3}+\frac{4}{3}=\frac{6}{3}=2$