This is my 13 reading notes in 2020.

It's true that I haven't read recently. I have read some books, but I haven't written notes for a long time.

While it was still hot last week, write down the notes of a book you read.

I accidentally brushed a book, but suddenly realized. If I can study math like that, will I become a mathematician?

Winter melon has started herding sheep in the summer vacation, and he refused all kinds of summer recess. Let him brush books and play with watermelons at home.

Mathematics study is a bit green and yellow. I think I have brushed all the math I should brush in the first grade, but I still like wax gourd. I haven't reported to the club, and I've been obsessed with math. Is it necessary to catch up? Is it necessary to talk about abstract content when children are still ignorant?

It was not until I saw this book that I let go of my entanglement and let my children enjoy themselves.

Mathematicians sigh that American mathematicians? Paul. A little book by Lakhart, about how to understand mathematics and how to let children walk into mathematics.

Mathematics is an art and rational music, similar to music and painting, not a mechanical brush and formula. What happened to modern mathematics education? What should real mathematics education do? The history of mathematicians, the birth of mathematical problems and the solution of mathematical problems, can we find the real practicality and charm of mathematics?

How to treat mathematics?

If you are a student, you can really do math to escape boredom and boredom.

If you are a teacher, your teaching should naturally come from your own experience in the jungle, not from the perspective of a fake tourist standing in a closed window carriage. If you have nothing to do with your topic, if it doesn't move you and give you goose bumps, then you must find another job. Honesty is very important at this point, otherwise I think our teacher will do great harm to our students unintentionally.

If you are not a student or a teacher, but a person who lives in this world and is looking for love and meaning like others, I hope I will try my best to give you a wonderful and pure glimpse and a harmless and enjoyable activity. For hundreds of years, it has brought indescribable happiness to many people.

A thousand words are not worth an example.

Look at the proof of a topic!

No matter where the vertex of the triangle is on the circumference, the triangle in the semicircle is a right angle.

By boring angle, isosceles triangle, triangle internal angle and 180 degree, equation substitution and other methods, it can be proved that it is a right angle. But this kind of proof is super boring and not straightforward.

Mathematics is to make simple things simple.

Wonderful proof: rotate this triangle around the circle for half a turn? Make it a quadrilateral in a circle. Because the triangle is completely rotated, the sides of this quadrilateral must be parallel, so this is a parallel self-deformation. But it is not a hypotenuse quadrilateral, because its two diagonals are the diameter of this circle, because they are equal in length, that is to say, it must be a rectangle, which is why its angles are right angles.

This is a relaxed and pleasant process. The key is the emergence of this idea, which is a very good idea.

Falling in love with mathematics is more important than mastering mathematics. A person's internal driving force often produces infinite power.

Set up a flag and write a math book that winter melon likes in the future.