Question

$( \sqrt{13} + \sqrt{5} )( \sqrt{13} - \sqrt{5} )$
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Answer 1

Question :

$\sf \small( \sqrt{13} + \sqrt{5} )( \sqrt{13} - \sqrt{5} )$

Formula :

$\boxed { \sf \small(a + b)(a - b) = {a}^{2} - {b}^{2} }$

Here,

• a → √13
• b → √5

Solution :

$\sf \small ( \sqrt{13} + \sqrt{5} )( \sqrt{13} - \sqrt{5} )$

$\sf \small \rightarrow {( \sqrt{13}) }^{2} - {( \sqrt{5} )}^{2}$

$\sf \small \rightarrow {(13)}^{ \frac{1}{2} \times \frac{2}{1} } - {(5)}^{ \frac{1}{2} \times \frac{2}{1} }$

$\sf \small \rightarrow13 - 5$

$\sf \small \rightarrow8$

• So the answer is 8

Answer 2

$\large { \fcolorbox{gray}{black}{ ✔\: \textbf{Verified \: answer}}}$

$( \sqrt{13} + \sqrt{5} )( \sqrt{13} - \sqrt{5} ) = 8$