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Prove that Tan ⁡3θ = (3 Tan θ−Tan^3 θ)/(1−3 Tan^2 θ)

Can someone please support me with this question, i just dont understand it i used tan(A+B)
Reply 1
Original post by aasimjk
Can someone please support me with this question, i just dont understand it i used tan(A+B)

Maybe use sin(3theta)/cos(3theta) ... You can get there with the tan addition formula, but the first way would be worth trying.
Reply 2
yes, one of the right tracks is using tan(A+B). think about how to split 3theta into two parts. then repeat tan(A+B) if one of the parts is not theta.

bit of algebra involved.

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