After the Integral Symbol we put the function we want to find the integral of called the Integrand and then finish with dx to mean the slices go in the x direction and approach zero in width. It is the binomial coefficient. If you are not logged into your Google account ex gMail Docs a login window opens when you click on 1.
A x x x.
An operator is a symbol that operates on a value or a variable. Delta refers to change in mathematical calculations. Common Symbols Used in Set Theory. In other cases it refers to the rate of change such as in a derivative.