Trigonometry+Concepts

Trigonometry Concepts
centered at the origin (0, 0) ||
 * Trigonometric Functions** - Also called circular functions. Trigonometric functions are commonly defined as [|ratios] of two sides of a right triangle containing the angle, and can equivalently be defined as the lengths of various line segments from a [|unit circle].
 * [[image:http://upload.wikimedia.org/wikipedia/commons/thumb/8/8f/Unit_circle.svg/186px-Unit_circle.svg.png align="center"]] ||
 * The unit circle. A unit circle is the circle of radius 1


 * Right Triangle Definitions**

All triangles are taken to exist in the [|Euclidean plane] so that the inside angles of each triangle sum to π [|radians] (or 180[|°]); therefore, for a right triangle the two non-right angles are between zero and π/2 radians (or 90[|°]).
 * One radian is the [|angle] [|subtended] at the center of a [|circle] by an [|arc] of [|circumference] that is equal in length to the [|radius] of the circle. The **radian** is a unit of plane [|angle], equal to 180///[|π]// [|degrees], or about 57.2958 degrees. It is represented by the symbol "rad" or, more rarely, by the superscript c (for "circular measure"). For example, an angle of 1.2 radians would be written as "1.2 rad" or "1.2c" (the second symbol can be mistaken for a degree: "1.2°").
 * It follows that the magnitude in radians of one complete revolution (360 degrees) is the length of the entire circumference divided by the radius, or 2//πr/////r//, or 2//π//. Thus 2//π// radians is equal to 360 degrees, meaning that one radian is equal to 180///π// degrees.


 * A Basic Right Triangle**








 * Slope Definitions**