Do I need to meet the requirements? Changing course

Hello I am currently a first year studying computer science at Brunel but I have really not enjoyed this year and I am thinking of changing course to economics. I wouldn't mind changing uni to maybe Greenwich/Westminster and redoing the year but I would really like to stay at Brunel. However they require grade B at A level in maths and I didn't take maths, I took a btec diploma in ict.

So my question is do you think they will still accept me for economics if they see I passed first year computer science at Brunel but I have no a level math or would I have to change uni? Thanks