Absolute Value Inequalities
Types of Absolute Value Inequalities
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Absolute Value Less Than:
- Example: ( |x| < 5 )
- Represents a distance that is no more than five units from zero.
- Algebraic interpretation: ( x ) is between (-5) and (5).
- Verification:
- For ( x = -3 ), ( |x| = 3 < 5 )
- For ( x = 4 ), ( |x| = 4 < 5 )
- Rule: For absolute value less than or less than or equal to, it's a "between" scenario.
- Interval Notation: ((-5, 5))
-
Absolute Value Greater Than:
- Example: ( |x| > 5 )
- Represents a distance that is more than five units from zero.
- Algebraic interpretation: ( x ) can be greater than (5) or less than (-5).
- Rule: For absolute value greater than or greater than or equal to, it's a "split" scenario.
- Interval Notation:
- ( (-\infty, -5) \cup (5, \infty) )
Key Concepts
- Absolute Value: Reflects the distance from zero.
- Between Scenario: When the absolute value inequality is less than, indicating a range between two values.
- Split Scenario: When the absolute value inequality is greater than, indicating two separate ranges outside a specific range.
- Interval Notation: Used to express the solution set of inequalities.
- "Union" is the same as "OR" for the solution sets.
Conclusion
- Understand the two main cases:
- Absolute value less than ("between" scenario)
- Absolute value greater than ("split" scenario)
- Practice these concepts to solve problems involving absolute value inequalities effectively.
In the next video, examples will be provided to illustrate these concepts further.