Prime sure is not first choice when it comes to symbolic operations.
The symbolics in Mathcad & Prime had undergone a lot of changes.
In older Mathcad versions a subset of Maple was used as symbolic engine. Later Maple was replaced for MuPad in Mathcad 14.
The reason was presumably that Maplesoft refused to licence its engine any further.
As a result, both Mathworks with MatLab and Mathsoft with Mathcad were forced to switch from Maple to another engine. Both selected MuPad, which was originally a free software developed by the University of Paderborn. The only difference was that Mathworks bought this software, made it commercial and continued to develop it, while Mathsoft and subsequently PTC had to pay licence fees for the MuPad core (which was hardly developed further over the years) to Mathworks.
PTC then decided to replace MuPad with a variant of the free FriCAS/Axiom system (first introduced in Prime 6) and to continue developing it itself.
However, MuPad and FriCAS have never been able to achieve the quality of Maple or Mathematica and are rather to be seen as a nice addition to the number cruncher Mathcad, whose proven strengths lie above all in dealing with units and natural input and display.
I played with your expression and simplified it down to
It was always hard to control the output of the symbolics. Sometimes changing the order the keywords are placed could help, sometimes throwing in "collect" or using "factor" instead of "simplify" would do the job.
I tried but could not make it simplify once a term was placed in the denominator.
Just out of curiosity I tried the very same in Mathcad 15 (with muPad) and this was the result
I am pretty sure that Mathcad 11 with Maple under the hood could simplify as well.
So I guess its now up to you to open a case with official PTC support and report this inability of the symbolics and hope that the engine will get improved in one of the upcoming versions.
