I've seen it. It's really good. You can search some video websites on Tudou first. If you read it online, you can see the actual situation and then decide whether to download it or something else.

Cai Gaoting's mathematics is quite suitable for learning from scratch, but attention should be paid to the digestion of knowledge in each class. His lecture will explain a lot of things you don't understand when reading, and the content is very comprehensive. You can go and have a look.

I'll show you the bean list of potatoes

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