Any point P with coordinates (\(x,~y\)) on the circumference of a circle can be joined to the centre (0, 0) by a straight line that forms the hypotenuse of a right angle triangle with sides of length ...

The formula to calculate the area of a circle, with radius \(r\) is: \(\text{area of a circle} = \pi r^2\) ...

Archimedes' method finds an approximation of pi by determining the length of the perimeter of a polygon inscribed within a circle (which is less than the circumference of the circle) and the perimeter ...