Definition
Unit interval
A unit interval is a number-line interval whose endpoints are exactly one unit apart.
Continue from this idea into connected AXIO math.
Boundary check: 3 − 2 = 1, so the highlighted span is exactly one unit.
What it means
Choose one point on the number line and move exactly one unit to the other endpoint. The interval from 3 to 4 and the interval from −2 to −1 are both one unit long.
Remember it
A unit interval is one full step along the number line.
Example
From 2 to 3, the distance is 3 − 2 = 1, so that span is a unit interval. If it is split into four equal parts, each part is 1/4 unit.
Watch for
The interval from 2 to 2.5 is only 0.5 unit long, so it is not a unit interval.
Common mix-up
The interval from 0 to 1 is the standard example, but in this card’s sense any number-line interval of length 1 is a unit interval.
Exact meaning
A unit interval is an interval on a number line with length 1, so its endpoints differ by exactly 1.