Mathematics for Everyone! A. V. Savvateev's Author Course on Stepik
Course in Russian. Alexey Savvateev introduces big mathematics without special preparation: invariants, infinities, continuity, self-similarity and the nature of numbers. 29 lessons, about 6.5 hours of video and 50 self-check tasks; suitable for school and university students interested in ideas beyond the school curriculum. Free and open at any time; a certificate is available on completion.
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