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Topic: Proving trigonometric identities
Replies: 32   Last Post: Jan 27, 2009 1:59 AM

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 Driveby Posts: 11 Registered: 11/27/07
Re: Proving trigonometric identities
Posted: Jan 26, 2009 12:07 PM

On Sun, 25 Jan 2009 21:49:25 -0800 (PST), Albert
<albert.xtheunknown0@gmail.com> wrote:

>On Jan 24, 9:02 pm, Albert <albert.xtheunkno...@gmail.com> wrote:
>> I agree: assuming sin x = -3 /4 is a step that one should get to (or
>> take the inverse cosec early on), x = 229, 311 degrees to the nearest
>> degree.

>
>The solve function on my calculator returns a strange answer, which
>indicates that there aren't actually any solutions to the original
>question 3cosec x + 4 = 0.
>So why doesn't it have any solutions?

How could someone know what you and your calculator are doing?

3 csc(x) + 4 = 0 has two zeros in [0, 2 pi),

x = pi + asin(3/4) and x = 2*pi - asin(3/4)

Date Subject Author
1/20/09 Albert
1/20/09 Angus Rodgers
1/20/09 Albert
1/20/09 Angus Rodgers
1/20/09 Albert
1/20/09 Angus Rodgers
1/20/09 Angus Rodgers
1/20/09 Guest
1/20/09 Angus Rodgers
1/20/09 Albert
1/20/09 Angus Rodgers
1/20/09 matt271829-news@yahoo.co.uk
1/21/09 Albert
1/21/09 matt271829-news@yahoo.co.uk
1/23/09 Albert
1/23/09 Angus Rodgers
1/23/09 Angus Rodgers
1/23/09 Passerby
1/23/09 Dave Dodson
1/24/09 Albert
1/24/09 Angus Rodgers
1/24/09 Albert
1/26/09 Albert
1/26/09 Driveby
1/26/09 Albert
1/26/09 A N Niel
1/27/09 Albert