Question

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Answer 1

Răspuns:

2. a = 12

3.    $\frac{1}{2}$

Explicație pas cu pas:

2.

$a = \sqrt{5} (\frac{1}{\sqrt{5} } +\sqrt{5} ) + (\sqrt{3} - \frac{1}{\sqrt{3} } )* 3\sqrt{3}$

$a =( \frac{\sqrt{5} }{\sqrt{5} } + \sqrt{5} *\sqrt{5} ) + 3\sqrt{3} *\sqrt{3} - \frac{3\sqrt{3} }{\sqrt{3} }$

$a = (1 + 5) + (9-3)$

a = 6 + 6

a = 12

3.

$\frac{\sqrt{13^{2} - 12^{2} } }{\sqrt{6^{2}+8^{2} } } = \frac{\sqrt{169 - 144} }{\sqrt{26 + 64} } = \frac{\sqrt{25} }{\sqrt{100} } = \frac{5}{10} = \frac{1}{2}$