Area of a circle Area of a circle In geometry, the area enclosed by a circle of radius is . Here the Greek letter represents a constant, approximately equal to 3.14159, which is equal to the ratio of the circumference of any circle to its diameter. One method of deriving this formula, which originated with Archimedes, involves viewing the circle as the limit of a sequence of regular polygons. The area of a regular polygon is half its perimeter multiplied by the distance from its center to its sides, and the corresponding formula (that the area is half the perimeter times the radius, i.e.
Circle MRT line an LRT line that goes from Paya Lebar to Buona Vista via Serangoon and Bishan to form Circle line Stage 3 and 4 in 2001. Circle line Stage 5 was finalised in February 2002 when Stage 4 was extended from Buona Vista to World Trade Centre to close up the link and to provide connectivity from the west to Sentosa, and it became the full Circle line in the end. Stations in Circle line that were a part of the original Marina line plans include Dhoby Ghaut, Bras Basah, Esplanade, Promenade, Nicoll Highway and Stadium. The part of the previously