Admissions tutors do expect a certain standard of academic English from applicants. The correct approach in this case would be to put the name in full and then the abbreviation in brackets afterwards if you plan on mentioning it again.*
You can't assume that they will know what the abbreviation means, especially given that there are sometimes multiple meanings for the same abbreviation. Expecting them to Google terms you use in your personal statement is not a good idea. You're assuming that they care enough to do so. If your personal statement is difficult to read, you've already put them off.**It's poor communication.*
On competitive courses, admissions tutors are often looking for reasons to cull applicants from the herd. Don't give them one.
I would advise writing the UK Maths Trust. It cuts out the two biggest words and there's no ambiguity. *