The idea of limit is the basic idea of calculus and a series of important concepts in mathematical analysis, such as continuity of function, derivative (maximum value is 0), definite integral and so on. These are all defined by the way of limit. Limit is the basis of solving higher mathematics problems.

2. Stones

Calculus is a branch of mathematics, which studies the differential and integral of functions and related concepts and applications. It is the basic subject of mathematics and has important applications in many fields.

3. Spatial analytic geometry

With the help of the concept of vector, geometry can be more easily applied to some natural sciences and technical fields. Therefore, after introducing spatial coordinate system, spatial analytic geometry introduces the concept of vector and its algebraic operation.