Question

cot 45/2= √2+1 prove that
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Answer 1

Answer:

$\huge \bf{Explanation} \\ \\ let \: \: \: \: A= \frac{45}{2} \\ \\ 2A = 45 \\ \\ using \: formula \\ \\ cos2A = 2 {cos}^{2} A</p><p>A - 1 \\ \\ cos45 - 1 = 2 {cos}^{2} A \\ \\ {cos}^{2} A= \frac{1}{ \sqrt{2} } - 1 \\ \\ {cos}^{2}A = \frac{1 - \sqrt{2} }{ \sqrt{2} } \\ \\ cos \: A = \sqrt{ \frac{1 - \sqrt{2} }{ \sqrt{2} } } \\ \\ hope \: it \: helps \: you.$