# Difference between revisions of "Intervals"

An interval is a set of numbers between upper and lower bound. To create an interval, type e.g. 2 < x < 3 in Input Bar. Interval in previous example is open. You can also define closed (2 ≤ x ≤ 3) and semi-closed (2 ≤ x < 3) intervals.

To determine whether number c belongs to interval r type r(c) into the Input Bar, the result will be a Boolean value. Generalization of intervals are Inequalities.

## Commands for intervals

• Min, Max, Midpoint for an interval with lower bound a and upper bound b return numbers a, b and \frac{a+b}2 respectively. The result doesn't depend on whether the interval is open, closed or semi-closed.
• Point returns a moveable point whose x-coordinate belongs to the interval and y-coordinate is 0.
• PointIn returns a moveable point whose x-coordinate belongs to the interval and y-coordinate may be changed arbitrarily.
• GeoGebra
• Help
• Partners