common factor reduction
- Subject: common factor reduction
- From: Alexander Klimov
- Date: Wed, 25 Jan 2012 12:46:47 +0200
On Tue, 24 Jan 2012, Marco Frigerio wrote:
> (%i..) trigreduce( -4*cos(q1)*sin(q2) + 4*sin(q1)*cos(q2) );
>
> sin(q2 + q1) sin(q2 - q1) sin(q2 + q1) sin(q2 - q1)
> (%o..) 4 (------------ - ------------) - 4 (------------ + ------------)
> 2 2 2 2
>
> I would really like to see
> - sin(q2 - q1) 4
>
> How can I achieve this?
%,ratsimp;
--
Regards,
ASK