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Interval Notation Calculator

Work with interval notation, union, and intersection

Operation Type

📐Interval Notation Basics

Parentheses ( )
Endpoint NOT included
(1, 5) means 1 < x < 5
Brackets [ ]
Endpoint IS included
[1, 5] means 1 ≤ x ≤ 5
Mixed Notation
Combine ( ) and [ ]
(1, 5] means 1 < x ≤ 5
Infinity
Always use parentheses
(-∞, 5) or (3, ∞)

💡Set Operations

Union (∪)
All elements in either set
(1,3) ∪ (2,5) = (1,5)
Intersection (∩)
Elements in both sets
(1,4) ∩ (2,5) = (2,4)

💼Applications

Mathematics
• Domain/range
• Solution sets
• Continuity
Statistics
• Confidence intervals
• Data ranges
• Distributions
Computer Science
• Valid ranges
• Set operations
• Data validation

Interval Notation Calculator