Question
Solve for $x : \cos (2x - 30^\circ ) = 0$
✓
Answer
$\cos (2x – 30^\circ ) = 0$
$\cos ( 2x – 30^\circ ) = \cos 90^\circ $
$2x – 30^\circ = 90^\circ $
$2x = 120^\circ $
$x = 60^\circ $
$\cos ( 2x – 30^\circ ) = \cos 90^\circ $
$2x – 30^\circ = 90^\circ $
$2x = 120^\circ $
$x = 60^\circ $
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