Algebra

Inequality to Interval Notation Converter

Easily convert inequality expressions to interval notation with our free online tool. Visualize intervals on a number line for a better understanding.

Result:

Interval Notation:

Visualization:

Learn Interval Notation

Interval notation is a way to represent sets of real numbers. It's commonly used to express the solutions to inequalities. Instead of writing inequalities like \(x < 5\) or \(x \geq -2\), we use parentheses and brackets to denote intervals.

  • Parentheses \((\,)\) indicate that the endpoint is not included in the interval (open interval). For example, \( (a, b) \) represents all numbers between \(a\) and \(b\), excluding \(a\) and \(b\).
  • Brackets \([\,]\) indicate that the endpoint is included in the interval (closed interval). For example, \( [a, b] \) represents all numbers between \(a\) and \(b\), including \(a\) and \(b\).
  • We use \(-\infty\) and \(\infty\) to represent intervals that extend indefinitely to the left or right. Infinity is always enclosed in parentheses because it\'s not a number and cannot be included.

Examples:

  • \( x < 5 \) is written as \( (-\infty, 5) \)
  • \( x ≤ -2 \) is written as \( (-\infty, -2] \)
  • \( x > 3 \) is written as \( (3, \infty) \)
  • \( x ≥ 0 \) is written as \( [0, \infty) \)
  • \( -1 < x ≤ \) is written as \( (-1, 4] \)

This tool helps you convert inequalities into interval notation and visualize them on a number line, making it easier to understand the range of values that satisfy the inequality.

Learn more about interval notation on resources like Math is Fun or Wikipedia.

Frequently Asked Questions

What is the Inequality to Interval Notation Converter?
The Inequality to Interval Notation Converter is an online Algebra calculator. You enter your values, and it returns the answer with the steps shown so you can follow along.
How accurate is the Inequality to Interval Notation Converter?
The solver uses a math engine that avoids the floating-point rounding errors you get from most hardware calculators. For typical homework and professional calculations, the results will match what you would get by hand.
Can I use the Inequality to Interval Notation Converter for professional Algebra projects?
Yes. The math behind it is standard Algebra, so the results are reliable for professional use. That said, always double-check that your inputs are in the right format before relying on the output.
Why use the Inequality to Interval Notation Converter instead of calculating by hand?
Manual calculation is slow and error-prone, especially with multiple steps. This tool does the arithmetic for you and shows each step, so you can catch mistakes before they carry forward.
How do I format my inputs for the Inequality to Interval Notation Converter?
Type your numbers into the input fields. Leave out units and symbols unless a field specifically asks for them. The solver handles the rest.