You have noticed somewhere that any formula which connects the given integral with another integral in which the integrand is of the same type but is of lower degree is called a Reduction Formula. Repeated or continuous application of reduction formula helps us to evaluate the given integral. This method of integration is called integration by successive reduction. Reduction formula can be easily derived using integration by parts i.e., product rule of integration. In this whole course, assume n, m are to be integers unless, otherwise stated.