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Question
Without using trigonometric tables, evaluate :
`sec 11^circ/("cosec" 79^circ)`
Solution
`sec 11^circ/("cosec" 79^circ)`
= `sec (90^circ - 79^circ)/("cosec" 79^circ)`
= `("cosec" 79^circ)/("cosec" 79^circ)` [`because sec (90 - theta) = "cosec" theta`]
= 1
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