Real number line

Definition

The real number line is a straight, continuous line that represents all real numbers ordered from left (negative) to right (positive). Each point on the line corresponds to a unique real number, including integers, fractions, and irrational numbers.

5 Must Know Facts For Your Next Test

1. The real number line extends infinitely in both directions.
2. Zero is at the center of the real number line, separating negative and positive numbers.
3. Every point on the real number line has a unique coordinate that represents a specific real number.
4. Intervals on the real number line can be closed or open, indicating whether endpoints are included.
5. $\sqrt{2}$ and $\pi$ are examples of irrational numbers located on the real number line.

Review Questions

• What separates negative and positive numbers on the real number line?
• How do you represent an interval that includes all numbers between -2 and 3, but not -2 and 3 themselves?
• Give an example of an irrational number that is represented on the real number line.

Related terms

Real Numbers: A set of numbers that includes all rational and irrational numbers. Real numbers can be found on the real number line.

Interval Notation: A way of representing subsets of the real number line using inequalities to show which points are included in an interval.

$\pi$: $\pi$ (Pi) is an irrational number approximately equal to 3.14159, which cannot be expressed as a simple fraction and has an infinite decimal expansion without repeating patterns.