In fact, there are also good calculus courses in China. Gong Sheng's concise calculus is ingenious and easy to understand. In fact, Gong Lao's books are of high quality.

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By the way, I would like to recommend a domestic advanced mathematics video course, which is Liu Zhongkan's advanced mathematics video. What I told TV University students at that time was not very deep, mainly omitting the proof of some theorems, but the thinking was really clear and suitable for getting started. I highly recommend it.

Of course, if you want to learn advanced mathematics under the background of Tongji Edition, the lecture of Advanced Mathematics 2 12 by Tang Jiafeng is also very good. In fact, Tongji's high math books are very general, and many students have also vomited, but Tang Lao's videos are really nice and easy to understand.