# Algebra 1 - Rational Functions

A rational function is a function whose rule is a quotient of polynomials in which the denominator has a degree of at least 1.  Today's free Algebra 1 video covers Rational Functions over 4 lectures with the wonderful Professor Edward Burger. In today's video you'll be identifying excluded values, which are values of x that make the function value y undefined in any function involving both x and y.  Then you'll jump to graphing rational functions when Professor Burger teaches about identifying asymptotes. An asymptote is a line that a graph gets closer to as the absolute value of a variable increases. To graph a rational function, you need to find the vertical and horizontal asymptote. And finally, in the very last lesson, Professor Burger will demonstrate a real world use of rational functions: cutting diamonds! Who knew that math was used in maximizing the brilliance of diamonds!? Watch all 4 lectures to get a great overview of rational functions. Just don't forget to click on the forward button to the left of the time stamp to move to the next lecture.

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