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Question
Evaluate:
`(3sin72^@)/(cos18^@) - sec32^@/(cosec58^@)`
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Solution
`(3sin72^@)/(cos18^@) - sec32^@/(cosec58^@)`
= `(3sin(90^@ - 18^@))/(cos18^@) - (sec(90^@ - 58^@))/(cosec58^@)`
= `(3cos18^@)/(cos18^@) - (cosec58^@)/(cosec58^@)`
= 3 – 1
= 2
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