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Question
find the value of: cos2 60° + sec2 30° + tan2 45°
Solution
cos2 60° + sec2 30° + tan2 45° = `(1/2)^2 + (2/sqrt3)^2 + 1^2`
= `(1)/(4) + (4)/(3) + 1`
= `( 3 + 16 + 12)/(12)`
= `(31)/(12)`
= `2(7)/(12)`
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