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Question
Find the value of sin ` 48° sec 42° + cos 48° cosec 42°`
Solution
sin 48° sec 42° + cos 48° cosec 42°
=`sin 48° cosec (90 ° - 42 °) + cos 48° sec (90° - 42°)
=` sin 48° cosec 48° + cos 48° sec 48°
=` sin 48° xx 1/ (sin 48°) + cos 48° xx 1/ ( cos 48 °)`
=1 + 1
=2
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