Derivative, also called derivative function value, also called wechat quotient, is an important basic concept in calculus and a local property of function. Not all functions have derivatives, and a function does not necessarily have derivatives at all points. If the derivative of a function exists at a certain point, it is said to be derivative at this point, otherwise it is called non-derivative. However, the differentiable function must be continuous; Discontinuous functions must be non-differentiable.
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. Calculus mainly includes limit, differential calculus, integral calculus and its application, and has become an important part of modern university education.
Development of derivative products:
/kloc-the development of productivity in the 0/7th century promoted the development of natural science and technology. On the basis of predecessors' creative research, great mathematicians Newton and Leibniz began to study calculus systematically from different angles. Newton's calculus theory is called "flow number". He called the variable flow and the rate of change of the variable flow number, which is equivalent to what we call derivative.
Newton's major works on "Flow Number Theory" include Finding the Area of Curved Polygon, Calculation Method Using Infinite Polynomial Equation, Flow Number Theory and Infinite Series. The essence of stream number theory is summarized as follows: his emphasis is on univariate function, not multivariate equation; It lies in the composition of the ratio of the change of independent variables to the change of functions; The most important thing is to determine the limit of this ratio when the change tends to zero.