View more at http://www.MathAndScience.com.
In this lesson, you will learn the six trigonometric functions and how to apply them to acute angles. The six trig ratios are sin (sine), cos (cosine), tan (tangent), cot (cotangent), sec (secant), csc (cosecant). These six trig functions are used in all branches of math, science, and engineering. The sine and cosine ratios are used to compare the horizontal and vertical sides of a right triangle to its hypotenuse. The tangent function is used to directly compare the sin and cos (vertical and horizontal) sides of the triangle. The tangent corresponds to the slope of a line. The cot, sec, and csc functions are just reciprocals of the other 3 trig functions. In all, there are 6 trigonometric functions that all students must learn.