Geometry
Semicircle Area
Area of half a circle.
Formula
Formula
A = ½ π r2
Variables
| Symbol | Definition | Type & range | Units | Role |
|---|---|---|---|---|
| r | radius | real number (ℝ) | — | input |
Try it yourself
Interactive calculator
Worked examples
Example 1
Givenradius r = 5
Result39.26990817
Example 2
Givenradius r = 2
Result6.283185307