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Trig Ratios and Special Angles  TOPIC_SOLVED

Trigonometric ratios and functions, the unit circle, inverse trig functions, identities, trig graphs, etc.
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Trig Ratios and Special Angles

Postby Seaweed09 on Wed Jan 25, 2012 11:55 pm

If sin x=-5/13, then determine sin(x/2). Should I use a compound angle formula for this?
Thanks!
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Re: Trig Ratios and Special Angles  TOPIC_SOLVED

Postby FWT on Thu Jan 26, 2012 9:57 pm

Seaweed09 wrote:If sin x=-5/13, then determine sin(x/2). Should I use a compound angle formula for this?
Thanks!

How about using the half-angle identity?
FWT
 
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