Summary: this article provides a brief description of definite integrals in geometry， physics and applications of elementary In this section， mainly uses the "micro-element" of the theory to solve real Definite integral is the overall amount of the distribution on the Because the whole is made up of local， so the actual question abstraction for definite integrals， must focus on the whole， starting from the For example， in seeking the irregular when the curved surface area of the quadrilateral， we tend to be converted to integral issues so as to achieve the purpose of solving (Seeking curved quadrilateral area element， and at intervals assumed office access point x， area element at the point x， is the "high" for f (x)， the rectangular area of wide differential， that (Rectangular area = height x width)， for example， the use of definite integrals of finding elliptic curve x=5cost，y=4sint perimeter as well as stereo volume， and so on， and briefly discusses simple applications of definite integrals in physics， and simple introduction to the basic use of definite integrals of elementary
