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How to Calculate the Area of a Circle
Formula
The area of a circle equals pi times the radius squared: A = pi x r².
This calculator also provides the circumference (2 x pi x r) and diameter (2r).
Common use cases:
- Calculating area of circular gardens or pools
- Pizza size comparison by area
- Engineering pipe cross-section calculations
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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