Geometric theorem:/%e9% AB% 98% E4% B8% AD% E6% 95% B0% E5% AD% A6% E7% AB% 9E% E8% B5% 9B% E4% B8% 93% E9% A2% 98% E8% AE%.

In fact, what is not involved in junior high school is tangent angle theorem, tangent theorem and projective theorem. After studying this book carefully, do more difficult questions and do more analysis. In fact, the plane geometry of the second measurement becomes very simple. There are books all over the world, so please find them yourself.

Please adopt it.