Question
If 2cosec 2 A – cot 2 A = 5 and
0 o < A < 90 o , then find the value of ‘A’.Solution
2cosec² A – cot² A = 5
Using, cosec² A = 1 + cot² A
We have, 2cosec² A – (cosec² A – 1) = 5
Or, 2cosec² A – cosec² A + 1 = 5
Or, cosec² A = 4
Or, cosec A = 2 or – 2
So, ‘A’ = 30° and 150°
Since, 0° < A < 90°, so ‘A’ = 30°
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