The number Pi, symbolized by a Greek letter, has a constant value that approximately equals 3.14159. Pi is an irrational number, which means it cannot be expressed as a common fraction, and it has an infinite decimal rep... More » Math Geometry

Cos(2pi) is equal to 1. The cosine function, cos(x), oscillates between 1 and -1 with a period of 2pi as x varies. By definition, cos(0) = 1, and the periodicity of the function means the cosine of all multiples of 2pi (... More » Math Geometry Trigonometry

The concept of the mathematical constant pi dates back approximately 4000 years to ancient Mesopotamia. Babylonian mathematicians found that the area of a circle was figured by taking the square of the radius, multiplied... More » Math Numbers
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To find out what a tangent equals, use the equation for a tangent, which is tan(degrees) = opposite / adjacent. This equation will determine what the tangent of an angle equals by using the triangle's opposite angle and ... More » Math Geometry

The number pi, which has a constant value that approximately equals 3.14, is an irrational number. It is a type or real number that cannot be expressed as a common fraction. It has an infinite or endless decimal represen... More » Math Numbers

To type the Greek letter pi in the Windows operating system, use the code alt+227. The alt key should be held down while typing the numerals. More » Technology Computers & Hardware Keyboard

The number pi is a mathematical constant, represented by the Greek letter π. Pi represents the ratio of a circle's circumference to its diameter. An interesting fact about pi would be that it is an irrational number, una... More » Math Numbers