Solve the following equation for A, if 2 2A = 1 - Vidyadip

Question

Solve the following equation for $A,$ if $2\cos2A = 1$

✓

Answer

$2 \cos 2 A = 1$
$\cos 2 A = \frac{1}{2}$
$\cos 2 A = \cos 60^\circ $
$2A = 60^\circ $
$A = 30^\circ $

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