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Question
Express the following in term of angles between 0° and 45° :
cosec 68° + cot 72°
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Solution
cosec 68° + cot 72°
= cosec(90° – 22°) + cot(90° – 18°) ...(∵ cosec(90° – θ) = sec θ and cot(90° – θ) = tan θ)
= sec 22° + tan 18°
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