Solve a Polynomial Inequality
You are asked to find the points that will make the inequality true.
Note:
If you didn't view the "Behavior of f(x)" slide presentation in
Lesson 2.2B, view it. Listen to the audio presentation:
Unlike solving a polynomial equation, which involves finding the value(s) of x (zeros), solving a polynomial inequality requires finding the intervals where the values of x will make the inequality true.
*** The solution set will include intervals rather than just points.***
Before you begin, always look at the inequality sign.
~ If it is greater than or equal to, ≥, then find positive regions between and include the function's zeros. The intervals would be included in brackets. [ ]
~ If it is greater than, >, then find positive regions between, but not including the function's zeros. The intervals would be included within parentheses. ( )
~ If it is less than or equal to, ≤, then find the negative regions between and including the function's zeros. The intervals would be included within brackets [ ]
~ If it is less than, <, then find the negative regions between, but not including the function's zeros. The intervals would be included within parentheses. ( )
Stated: The inclusion of the zeros will be recorded only if the inequality has an equal sign included with the inequality greater than/less than.
Check your understanding
The activity below will check your understanding of using the number line to find the solution set for polynomial inequalities.
Click on the activity to work through this interactive presentation.