Solve Trig Identity with Cot 3u Problem

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To solve the trig identity involving cot(3u), it is suggested to express cot(3u) as 1/tan(3u) and utilize the triple angle formula for tan(3u) for simplification. Participants emphasize the importance of knowing the entire problem statement to provide accurate assistance. Additionally, breaking cot(3u) into cot(u + 2u) and applying sum formulas is recommended as an alternative approach. The discussion highlights the various methods available for tackling such trigonometric identities. Providing the complete expression or question is crucial for effective problem-solving.
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hey guys just had a test, i got a trig proof prob with cot 3u, just wondering how u break it up. thanks
 
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Break it up into what?

the most I can tell you is that cot(3u)=1/tan(3u)

and one can use the triple angle formula for tan3u and get another equivalent expression.
 
I take it you know \cot u=\frac{\cos u}{\sin u}. We could express this in a whole lot of ways. So you may want to give us the entire question or the expression you are working towards.
 
As rockl.freak667 and Cyosis said, there are many different ways to "break up" such a function? What, exactly, was the statement of the problem?

I think I would be inclined to write it as cot(3u)= cot(u+ 2u) and use "sum" formulas. That's because I don't happen to remember offhand the "triple angle formula" rock.freak667 mentioned!
 

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