[Maxima-discuss] sqrt(1-sin(t)^2) -> sqrt(1-sin(t))*sqrt(sin(t)+1)

[Eduardo O. <edu...@gm...>]

Hi list,

if I execute this

  display2d : false;
  ex0 : 'integrate(s*sqrt(1-s^2), s);
  ex1 : changevar(ex0, s=sin(t), t, s);

what I get is:

  (%i1) display2d : false;
  (%o1) false
  (%i2) ex0 : 'integrate(s*sqrt(1-s^2), s);
  (%o2) 'integrate(s*sqrt(1-s^2),s)
  (%i3) ex1 : changevar(ex0, s=sin(t), t, s);
  (%o3) 'integrate(cos(t)*sqrt(1-sin(t))*sin(t)*sqrt(sin(t)+1),t)

but I am trying to prepare material for a course on basic integration
techniques, so the style of simplification that I need is different...
this factorization is "bad":

   sqrt(1-sin(t)^2)
   ->  sqrt(1-sin(t))*sqrt(sin(t)+1)

Questions:

  1) how do I tell Maxima to not factor that sqrt?
  2) how do I tell Maxima to do this instead?

     sqrt(1-sin(t)^2)
     ->  cos(t)

Thanks in advance!
  Eduardo Ochs
  http://angg.twu.net/eev-maxima.html