Introduction - If you have any usage issues, please Google them yourself
For a definite integral function, in most cases, the primary function of the integrand is difficult to be expressed by elementary function, so it can use the Newton Leibniz formula of calculus integral calculation is a rare chance. In addition, the integrand in many practical problems is often a list function or other form of discontinuous function, and the definite integral of such functions can not be solved by indefinite integral method. For these reasons, the theory and method of numerical integration has been the basic subject of computational mathematics. Master of mathematics made outstanding contributions to the calculus, such as I. Newton, L. C.F. Gauss, Euler, Lagrange and others in the field of numerical integration to make their respective contributions, and laid the theoretical foundation of this branch.