Week 14 – Rational Expressions

A rational expression is a fraction in which the numerator and the denominator are polynomials.

Examples of rational expressions:

Non-permissible values are like restrictions. The denominator of a fraction cannot be 0 so we have to give restrictions for all values that make the denominator 0.

For example, the non-permissible values for the equation,  are 0 and 5, so,  and .

The first step to simplifying a rational expression is to factor the numerator and the denominator if it isn’t factored already. Then state the restrictions.

Cancel out the common factors from the numerator and the denominator.