TRyHarD
The best thing you could do is find out what content you need to learn then finding physical resources like textbooks like going to libraries then learning from there.
For RC and VR expand your vocabulary like using vocabulary.com (highly recommend).
Content in Mathematics: Number, Algebra, Measurement, Geometry, Statistics and Probability
Hope that helped.
But defs finding physical textbooks is what I did for two superiors: Maths and NR
