Re: [Maxima-discuss] Simplification of a trigonometric or exponentialized term

[Roland S. <sal...@gm...>]

> -----Original Message-----
> From: Raymond Toy [mailto:toy...@gm...]
> Sent: Tuesday, July 18, 2017 9:21 PM
> 
> Here is one way.  Take Barton's result:
> 
> c: (sqrt(sqrt(5)+5)*(3*sqrt(2)*sqrt(5)-5*sqrt(2))*%i)/20
> c^2;
> ratsimp(sqrt(expand(%))),algebraic;
> 
> => sqrt(5-2*sqrt(5))*%i/sqrt(5)
>
> The c^2 and expand is a hack to get maxima to multiply the contents of the sqrt together.  This really only works
> because the imagpart is positive.  Otherwise, we probably would have gotten the wrong sign.
> 

True. Unfortunately, my problem consists of 4 such expressions, and two of them are negative imaginary numbers. Take for example the expression -c. The sign is lost. Is there another hack to simplify the general case? Or would I have to write my own routine that memorizes the sign and adjusts it at the end accordingly?

PS: Stavros' general algorithm I did not dare to ask about this new situation yet ...

Best regards,
Roland