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Trigonometry
Trig
The study of triangles, with emphasis on calculations involving the lengths of sides and the measures of angles. Trigonometry is also known as trig.
Trigonometry is based on the six functions sine, cosine, tangent, cosecant, secant, and cotangent. Trig also includes studies of the properties of these functions and their graphs.
Finally, trig involves the analysis of circles and periodic motion.