The most common functions used in trigonometry are sine, cosine and tangent and are most commonly used when calculating the angle measurements in right triangles. Trigonometry generally bases angle measurements on 90 and 180 degree angles. An angle that is 90 degrees is called a right angle while an angle that is 180 degrees is a straight line.
When studying trigonometry, ratios of pairs of the sides are triangles are used. These ratios are considered functions. These ratios are categorized into six functions, which are listed on a trigonometric function chart and called "sin," "tan," "sec," "cos," "cot" and "csc." These functions are used to calculate the sides of triangles. Every ratio has an inverse ratio as well; which are often needed when calculating angles.
Trigonometric functions are also used for circles using coordinates of x and y. The six functions listed for a circular chart are also called the same names: sin, tan, sec, cos, cot and csc. Sin, cos and tan are the most popular. Because these are coordinates, the signs are either positive or negative.
In many scientific calculators, trigonometric charts are not needed. Most trigonometric values are easily found through the use of a calculator. The calculators contain all the needed tables, logarithms and rules. A person must simply enter the information and press the correct buttons. After doing this, the calculator performs the necessary calculations and a person can easily find the answers. The hardest part with this is knowing how to enter the information correctly.