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Question
Find the value of angle A, where 0° ≤ A ≤ 90°.
sin (90° – 3A) . cosec 42° = 1
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Solution
sin (90° – 3A) . cosec 42° = 1
`cos3A. 1/(sin42^circ) = 1`
cos 3A = sin 42°
= sin (90° – 48°)
= cos 48°
3A = 48°
A = 16°
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