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Question
Without using trigonometric tables, evaluate :
`sin 16^circ/cos 74^circ`
Solution
`sin 16^circ/cos 74^circ`
= `sin (90^circ - 74^circ)/cos 74^circ`
= `cos 74^circ/cos 74^circ` [∵ sin (90-θ) = cos θ ]
= 1
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