Secondly, the summation of double series is also widely used in solving practical problems. For example, in physics, engineering, economy and other fields, we often encounter some problems involving infinite series and infinite series, such as solving the limit of some physical quantities and calculating the sum of some economic indicators. These problems can be effectively solved by the method of summation of double series, which provides theoretical support for solving practical problems.
In addition, the summation of double series is closely related to other branches of mathematics. For example, it is closely related to calculus, real analysis and complex analysis. In calculus, we can study the continuity and differentiability of functions through the summation of double series. In real analysis and complex analysis, the summation of double series can help us to study the properties of analytic functions and the convergence of series.
In a word, the summation of double series plays an important role in mathematical analysis. It is not only the basis of learning infinite series and infinite series, but also plays a key role in solving practical problems and cross-research with other branches of mathematics. Therefore, the research on the summation of double series has important theoretical value and practical application value.