Can I still do Maths?

With a Maths degree, they might not expect me to do the introductory Maths courses. But my A levels were in 1969 and my degree in 1972. I looked at OU assessment exercises for maths. Some of it I can still do (algebraic manipulation). Some of it I can do but painfully slowly (about half of the rest). And some I have done in the past but can't remember anything about. Eigen vectors, anybody? I need to do all the maths courses because I want to feel solid at least at that part of the course. And I would be humiliated if I had problems with Maths on the higher levels of the course.