Go to content
For a circle with radius r, the area = \pi r^2 and perimeter = 2 \pi r.
On a calculator \pi \times 4.27^2 is found by π×4.27=

You can get a better display of the maths by downloading special TeX fonts from jsMath. In the meantime, we will do the best we can with the fonts you have, but it may not be pretty and some equations may not be rendered correctly.

Glossary

circle

a conic curve with equation (x-a)²+(y-b)²=r²

union

The union of two sets A and B is the set containing all the elements of A and B.

Full Glossary List