The quotient obtained by dividing the distance from the vertex of an angle to another arbitrary point on the terminal edge of the angle by the non-zero ordinate of the following point, the vertex of the angle coincides with the origin of the plane rectangular coordinate system, and its starting edge coincides with the positive direction of the X axis, which is recorded as cscx. The ratio expression of cotangent and sine is reciprocal. The function of cotangent is like odd function, which is a periodic function.
Extended data
Trigonometric function is a common function about angle in mathematics. The trigonometric function relates the internal angle of a right triangle to the ratio of two sides, and can also be defined by the lengths of various line segments related to the unit circle equivalently. Trigonometric function plays an important role in studying the properties of geometric shapes such as triangles and circles, and is also a basic mathematical tool for studying periodic phenomena.
In mathematical analysis, trigonometric function is also defined as the solution of infinite series or specific differential equation, which allows the value to be extended to any real value or even complex value.
Common trigonometric functions are sine function (sin), cosine function (cos) and tangent function (tan or tg). In navigation, surveying, engineering and other disciplines, other trigonometric functions such as cotangent function, secant function, cotangent function, dyadic function, semi-dyadic function and so on will be used.
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