The ∫ symbol has the meaning Integral. It belongs to the category Mathematical Symbols. The integral sign is used in integral calculus and thus belongs to the mathematical analysis. The integral is also a generic term for the indefinite and the definite integral. If you have given the function f and you should now calculate the area under the function f from 0 to 2, then you use the integral calculus. When calculating the integral, you always add the upper and lower limits to the integral symbol, which are usually specified with a and b. The spelling could look something like this: ∫ f(2x + 4)dx
If you want to use the integral symbol indicating the boundaries, you must using a special program that specializes in representing mathematical signs. For example, you could use the LaTeX software package.