# Area of a circle

## Calculates the area and circumference of a circle given the radius or diameter.

area S
circumference L

 $\normal Circle\\\vspace{5}(1)\ diameter:\hspace{45} R=2r\hspace{30}r:\ radius\\(2)\ area:\hspace{80} S=\pi r^2=\pi({\large\frac{R}{2}})^2\\(3)\ circumference:\ L=2\pi r=\pi R\\$

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