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by **jinxt** on Wed Apr 22, 2009 12:39 am

I've searched my whole trig book, looked through all my notes but still, I can't seem to figure this problem out! Can anyone give me some help? It would greatly be appreciated!

Show that: 2arctan(1/2)=arctan(4/3)

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by **Martingale** on Wed Apr 22, 2009 1:41 am

jinxt wrote:I've searched my whole trig book, looked through all my notes but still, I can't seem to figure this problem out! Can anyone give me some help? It would greatly be appreciated!

Show that: 2arctan(1/2)=arctan(4/3)

if you apply the tangent to both sides and use the formula...

$\tan(\alpha \pm \beta) = \frac{\tan( \alpha) \pm \tan (\beta)}{1 \mp \tan (\alpha) \tan( \beta)}$

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How to show 2arctan(1/2)=arctan(4/3)

How to show 2arctan(1/2)=arctan(4/3)

Re: How to show 2arctan(1/2)=arctan(4/3)