AI Age Knowledge. Peter Chew Triangle Diagram My Research is to create new discoveries (new rules, new methods, theorems or diagrams) to supplement the information needed to complete certain areas of mathematics. New discoveries can make solving certain mathematical problems easier, more direct and more accurate, which can help us in mathematics teaching and enable the next generation to solve the same problems directly, more easily and more accurately. By using the newly discovered Peter Chew rule and triangle diagram, all problems in the topic solution of triangle can be solved directly, easily and accurately. Because some areas of mathematics are still incomplete today, this makes current technical tools such as online calculators unable to solve certain mathematical problems. This will cause students to reduce their interest in using today's technological tools and hinder the promotion of effective mathematics learning. In order to solve the above problems, I applied my new discovery to the AI Age Calculator, PCET calculator https: //youtu.be/9m7mc0UTsSw. The new discovery enables the PCET calculator to solve all the problems in this particular field of mathematics. When the future epidemics such as Covid-19 occur in the future, it can effectively help mathematics teaching, especially for students studying at home. This book can be used not only for Engineering Mathematics students, but also for high school students, because " Solution of Triangle " is important chapters in Engineering Mathematics and high school Advanced Mathematics. It is similar to calculus and is an important chapter in Engineering Mathematics and high school Advanced Mathematics.