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

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 matt271829-news@yahoo.co.uk Posts: 2,136 Registered: 1/25/05
Re: Proving trigonometric identities
Posted: Jan 20, 2009 10:53 PM

On Jan 20, 9:17 am, Albert <albert.xtheunkno...@gmail.com> wrote:
> It has to be the same otherwise I can't write:
>
> cosx / (1-sinx) = (1+sinx)/cosx
> (cos^2)x = (1+sinx)(1-sinx)
> ..``..``.= 1 - (sinx)^2
> (sin^2)x + (cos^2)x = 1

You should never write (sin^2)x to mean sin^2(x).

I have never seen the notation (sin^2)x and I have no idea what it
might mean, except as a mistake for sin^2(x).

I do not like sinx. With single-term arguments it is permissible to
omit the brackets, but in that case you should in plain-text leave a
space -- as in sin x and (sin x)^2.

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