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Topic: Trigonometry - Proving trigonometric identities
Replies: 3   Last Post: Dec 19, 2004 8:36 PM

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 Kevin Karplus Posts: 5 Registered: 12/6/04
Re: Trigonometry - Proving trigonometric identities
Posted: Dec 19, 2004 8:34 PM

In article <ksnbs0lc0nei5ff1jue4m6gg10u7bkjg2c@4ax.com>, Robert Evans wrote:
> How do you prove the following identity:
>
> cosA * cotA + sinA = cscA

Try multiplying both sides by sin(A) and simplifying the
fractions---see it it looks more familiar then.

------------------------------------------------------------
Kevin Karplus karplus@soe.ucsc.edu http://www.soe.ucsc.edu/~karplus
Professor of Biomolecular Engineering, University of California, Santa Cruz
(Senior member, IEEE) (Board of Directors, ISCB starting Jan 2005)
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Date Subject Author
12/19/04 Kevin Karplus
12/19/04 Jeffrey Turner
12/19/04 George Cox