Question

$(5 - \sqrt{2) (5 + \sqrt{2)} }$
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Answer 1

Question :-

Solve :-

$\sf (5 - \sqrt{2}) (5 + \sqrt{2})$

Answer :-

By using the identity -

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

$\sf (5 - \sqrt{2}) (5 + \sqrt{2})$

• $\sf a = 5$
• $\sf b = \sqrt{2}$

$\sf = 5^2 - (\sqrt{2})^2$

$\sf = 5^2 - 2$

$\sf = 25 - 2$

$\sf = 23$

$\boxed{\sf (5 - \sqrt{2}) (5 + \sqrt{2}) = 23}$