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

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

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
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The mathematical constant pi has many uses, most of which are associated with the circle or circular objects. Often, pi is used for geometric purposes, such as calculating the area of a circle or the volume of a sphere. More » Math Geometry

The formula for the area of any triangle equals 1/2 the base times the height. For a right triangle, this is easy to remember ,since a right triangle is half of a rectangle on one side of its diagonal, and the area of a ... More » Math Geometry

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

Euclid was a Greek mathematician who is famous for writing a series of 13 books called Elements about geometry and other mathematical concepts. His concepts and explanations of plane geometry, which take up approximately... More » Math Geometry