In this article I will explain what are Integral Equations, how those are structured and what are certain types of Integral Equations. What is an Integral Equation? An integral equation is an equation in which an unknown function appears under one or more integration signs. Any integral calculus statement like — $ y= \int_a^b \phi(x) dx$ can be considered as an integral equation. If you noticed

# Multiple integral

Topic Beta & Gamma functions Statement of Dirichlet’s Theorem $ \int \int \int_{V} x^{l-1} y^{m-1} z^{n-1} dx dy ,dz = \frac { \Gamma {(l)} \Gamma {(m)} \Gamma {(n)} }{ \Gamma{(l+m+n+1)} } $ , where V is the region given by $ x \ge 0 y \ge 0 z \ge 0 x+y+z \le 1 $ . Brief Theory on Gamma and Beta Functions Gamma Function If we