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Question
If tan θ = 3 find tan 3θ
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Solution
tan θ = 3
tan 3θ = `(3 tan θ - tan^3 θ)/(1 - 3 tan^2 θ)`
`= (3(3) - (3)^3)/(1 - 3(3)^2)`
`= (9 - 27)/(1 - 27)`
`= (- 18)/(- 26) = 9/13`
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