The sign function is used to represent the absolute value of a number when used in trigonometry. It is also referred to as the signum function in math.
The understanding of shapes and angles.
usually referred as the function COS
Neither, it is a mathematical discipline.
Trigonometry is the study of the relationships between the sides and the angles of triangles and with the trigonometric functions, which describe those relationships.
sine, cosine, tangent, cosecant, secant, cotangent.
The basic circular functions are sine, cosine and tangent. Then there are their reciprocals and inverses.
The reciprocal of any function f(x) is 1/f(x) provided that f(x) is non-zero. That applies to all relations in mathematics, not just trigonometry.
The period of a trigonometric function, since it depends on the angle of a ray centered in a unit circle, is 2 pi radians or 360 degrees.
plane trigonometry spherical trigonometry
The main kinds are plane trigonometry and solid trigonometry. The latter will include trigonometry in hyper-spaces.
Trigonometry is a mathematical tool that is part of various other forms of mathematics and is used in all sorts of science and engineering; for example, the sine function in trigonometry turns out to be applicable to sine waves that are formed by alternating electrical currents which are used to power your computer which is the basic tool that you use in information technology.