Trigonometrical function

Related to Trigonometrical function: exponential function, Inverse trigonometric function
a quantity whose relation to the variable is the same as that of a certain straight line drawn in a circle whose radius is unity, to the length of a corresponding are of the circle. Let AB be an arc in a circle, whose radius OA is unity let AC be a quadrant, and let OC, DB, and AF be drawnpependicular to OA, and EB and CG parallel to OA, and let OB be produced to G and F. E Then BD is the sine of the arc AB; OD or EB is the cosine, AF is the tangent, CG is the cotangent, OF is the secant OG is the cosecant, AD is the versed sine, and CE is the coversed sine of the are AB. If the length of AB be represented by x (OA being unity) then the lengths of Functions. these lines (OA being unity) are the trigonometrical functions of x, and are written sin x, cos x, tan x (or tang x), cot x, sec x, cosec x, versin x, coversin x. These quantities are also considered as functions of the angle BOA.
See under Function.

See also: Function, Trigonometric

References in periodicals archive ?
Using the orthogonal characteristic of two beams from a laser head, the seismic signals are expressed as a form of intensity signal, which is represented as a trigonometrical function. Hence, the seismic signal can be detected using the laser interferometer.
The expressions (2) and the second time derivatives for the torsional vibration amplitudes are introduced in the differential equation system, and by simplification with the trigonometrical function cos[[OMEGA].sub.x]t-[epsilon]) we obtain the algebraic equation system (Balcau& Arghir, 2009).
We consider CAM of the special integral splines with hyperbolic trigonometrical functions for solving the 3-D initial boundary-value problem in z-direction [10].