Since circular creations appear throughout nature, no man can be credited with the invention of the circle. From the cross-section of a plant stem to the moon and the sun, circles appear everywhere in nature. More »

The unit circle does not have a known creator but was rather an amalgamation of different ideas from early astronomers and mathematicians. Contributors to the technology include the Babylonians, the Egyptians and the Gre... More »

Brahmagupta, a Hindu mathematician and astronomer, first used a dot underneath other numbers to represent the number zero in 628 A.D. He was the first to develop additive and subtractive operations that use zero. More »

Optical illusions have been found in cave paintings, so an optical illusion is not considered an invention but instead is the result of man imitating the geometric forms seen in nature through architecture and art. Arab ... More »

A circle is not a polygon because it does not conform to the definition of a polygon. The definition of a polygon is a closed figure formed by straight lines or straight sides. Although the circle is a closed figure, it ... More »

The formula for the area of a circle is pi multiplied by the radius of the circle squared. The radius of the circle is the length of a straight line stretching from the center of the circle to the line of circumference. ... More »

To calculate a circle's diameter from its circumference, one should divide the circumference by the constant pi, which is an irrational number approximately equal to 3.14159265358979. More »