I have posted a video on rational expressions and rational functions.
This video begins with examples of rational expressions. I also discuss the valid values of a rational express; the denominator can never have a value of zero. Consequently, this discussion is on the domain of a rational expression and rational function. I discuss how to write the domain in interval form.
The next objective is how to reduce a rational expression. Reducing rational expressions is just like reducing rational numbers. We have to factor the numerator and factor the denominator, and cancel like terms.
The video ends with evaluating rational functions and an application of rational functions relating to the average cost function.
As always, I hope you find this video helpful. Please feel free to leave any comments and suggestions to make a better product.