Is there an interactive math course?

Question

Mathematics

Tell me, I want to refresh the course of mathematics, thoroughly forgotten for 8 years. The goal is to understand the course of electrical engineering, to be able to calculate DC-DC converters, for example. What you need - you need, preferably, an interactive online course on mathematical analysis, with the possibility of self-testing, which is necessary to understand the degree of assimilation of the material. It is possible in English, but not very difficult.

Answer 1

khanacademy.org