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Question
Find the magnitude of angle A, if tan A - 2 cos A tan A + 2 cos A - 1 = 0
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Solution
tan A – 2 cos A tan A + 2 cos A – 1 = 0
tan A – 2 cos A tan A = 1 – 2 cos A
tan A ( 1 – 2 cos A ) – (1 – 2 cos A )= 0
(1 – 2 cos A) (tan A – 1) = 0
1 – 2 cos A = 0 and tan A – 1 = 0
cos A = `(1)/(2)` and tan A = 1
A = 60° and A = 45°
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