We also define the domain and range of a function. A function relates an input to an output. The same happens for other inputs.
It usually connects two or more quantities with an equal to sign.
Formula - mathematics a standard procedure for solving a class of mathematical problems. Typical examples are functions from integers to integers or from the real numbers to real numbers. This tree grows 20 cm every year so the height of the tree is related to its age using the function h. A Formula is an equation designed by a user in Excel while a Function is a predefined calculation in the spreadsheet application.