Lesson 1
1. Lesson 1
1.7. Explore 3
Module 6: Rational Expressions
Non-Permissible Values
A rational expression is not defined when the expression’s denominator is zero. Therefore, any value of the variable that would result in a denominator of zero is considered a non-permissible value.
Try This 2
For each of the rational expressions in the table, determine the non-permissible value(s). You can check your answers by using your calculator.
| Rational Expression | Non-Permissible Value(s) of x |
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Save your response in your course folder.
Turn to “Example 1” on page 312 in the textbook to see how you can determine non-permissible values for rational expressions that are similar to the expressions in Try This 2. Look for answers to the following questions:
- What equations are used to find non-permissible values?
- Why is it not necessary to determine when numerators are equal to zero?
- How does factoring the denominator make it easier to identify non-permissible values?
Look back at your answers to Try This 2. After reading through “Example 1,” are there any answers you would change? Why?
Self-Check 1
Complete Non-Permissible Values Self-Check to check your understanding of the concepts presented so far.