correct/simplify Content MathML

Hi!

I'm looking for a way to correct/simplify mathematical expressions encoded in MathML. (content)

The program I'm working on, should be able for example to make no difference between "x+2" and "x+1+1" and if possible also between "sin2x" and "2cosxsinx".

For this I have been trying to find a program or an XSLT that converts MathML into other kind of mathematical markup so that I can process it afterwards. 

for example convert

<math>
   <apply>
      <plus/>
      <ci>x</ci>
      <cn>2</cn>
   </apply>
</math>

into (x+2) 

But I haven't found anything!

I thought of writing an XSL for myself, but I would need to convert prefix (from MathML) to infix notation and this seems pretty difficult to me. 


These are things, that Mathematica and Maple can do. But how?

Any idea?

Thanks!

Ana