The cleaner the math, the cleaner the resulting code.This chapter reviews various tools from high school andcollege mathematics and is designed to be used more as a reference than as a tutorial.

1 Sets and Mappings

• 集合的概念

  a ∈ S，Cartesian product(笛卡尔积)A × B，固定符号表：

  

• 函数相关概念

  

1.1 Inverse Mappings

• 满射 / 双射 /单射相应的概念

  

• 反函数存在的对应条件是原函数是双射函数

1.2 Intervals

• 开集闭集的区别 间隔与集合之间相似的操作

  

  

1.3 logarithm

2 Solving Quadratic Equations

基本的求解二次方程定理（判断是否有根）和相应的求根公式：

$$ x = \frac{-B \pm \sqrt{B^2-4AC}}{2A} $$

3 Trigonometry

In graphics, we use basic trigonometry in many contexts. Usually, it is nothing too fancy, and it often helps to remember the basic definitions.

3.1 Angles