Express tan3x in terms of tanx.

Trigonometric ratios and functions, the unit circle, inverse trig functions, identities, trig graphs, etc.
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Express tan3x in terms of tanx.

Postby marty.frmn » Sun Oct 25, 2009 7:29 pm

Express tan3x in terms of tanx....
Answer: tanx(3-tan^2x) / 1-3tan^2x
i have used it like sin3x/cos3x and then i use the formula for both.... but then i get stuck in between....

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Postby stapel_eliz » Mon Oct 26, 2009 12:09 am

I think you might want to try using a summation formula...? Re-state tan(3x) as tan(x + 2x), and see where that leads.

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