The equation of a straight line can also be written in the form \(f(x) = mx + c\). This is called function notation and is just another way of expressing the relationship between two variables.

Composite functions are made when the output from one function is used as the input of another function. The names of the functions are written next to each other, with the function that is used first ...

Buckley–Leverett theory and Welge equation is one of the most widely used methods for predicting fluid transport in porous media. However, the average water saturation in Welge equation is a function ...