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Question
Find the magnitude of angle A, if 2 sin A cos A - cos A - 2 sin A + 1 = 0
Solution
2 sin A cos A – cos A – 2 sin A + 1 = 0
2 sin A cos A – cos A = 2 sin A – 1
(2 sin A – 1) cos A – (2 sin A – 1) = 0
(2 sin A – 1) = 0 and cos A = 1
sin A =`(1)/(2)` and cos A = cos 0°
A = 30° and A = 0°
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