Question

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

Answer:

$Value \: of \:(5 + \sqrt{5} )(5 - \sqrt{5} )=20$

Step-by-step explanation:

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

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

/* By algebraic identity:

(a+b)(a-b)= a²-b² */

$=25-5\\=20$

Therefore,

$Value \: of \:(5 + \sqrt{5} )(5 - \sqrt{5} )=20$

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