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Question
Without using tables, evaluate the following: tan230° + tan260° + tan245°
Solution
tan230° + tan260° + tan245°
tan30° = `(1)/sqrt(3)`
tan60° = `sqrt(3)`
tan45° = 1
tan230° + tan260° + tan245°
= `(1/sqrt(3))^2 + (sqrt(3))^2 + 1`
= `(1)/(3) + 3 + 1`
= `(1 + 9 + 3)/(3)`
= `(13)/(3)`.
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