Definite Integral: Riemann Sum

This lecture covers the definition of the definite integral for a continuous function over a closed interval, introducing Riemann sums as approximations of the area under the function's graph. It explains the concept of a finite sequence as a subdivision of the interval, leading to the calculation of Riemann sums. The instructor demonstrates the process of determining Riemann sums using different subdivisions and discusses the implications of the function's continuity on the accuracy of the approximations.