More Lessons: http://www.MathAndScience.com Twitter: https://twitter.com/JasonGibsonMath In this lesson, you will learn what an exponential function is and what they are used for in math and science. An exponential function is a function where the independent variable x is in the exponent of a number. The base can be any number, and the shape of the exponential graph will look different depending on the number chosen for the base. If the base is positive, then the exponential graph will grow showing exponential growth. If the base is negative, then the graph will get smaller as x increases, showing an exponential decay. It is important to understand the formula for exponential growth and decay, and how to graph these functions, because they are very common in math, science, and engineering.