Objective
To simplify rational expressions
An expression of the form
Essential Understanding The simplified form of a rational expression is like the simplified form of a numerical fraction. The numerator and denominator have no common factor other than 1. To simplify a rational expression, divide out common factors from the numerator and denominator.
Like a numerical fraction, a rational expression is undefined when the denominator is 0. A value of a variable for which a rational expression is undefined is an excluded value.
What is the simplified form of
Should you use the simplified form to find excluded values?
No. You must check the original expression to see which values of x make the denominator 0.
The denominator of the original expression is 0 when