Suppose the length of the perpendicular is y and of base is x. 2/2015 COPYRIGHT 2015 CARR LANE MFG. And I found myself Learning something new everyday Table of Contents. Let us see how are these ratios or functions, evaluated in case of a right-angled triangle. Trigonometry Table: Trigonometric Formula, Ratio And Angle. Consider a right-angled triangle, where the longest side is called the hypotenuse, and the sides opposite to the hypotenuse are referred to as the adjacent and opposite sides. The concept of unit circle helps us to measure the angles of cos, sin and tan directly since the centre of the circle is located at the origin and radius is 1. The sides of the right-angled triangle are designated a and b and the hypotenuse, c. The angles opposite each of these sides are designated A and B, respectively. Historically, the earliest method by which trigonometric tables were computed, and probably the most common until the advent of computers, was to repeatedly apply the half-angle and angle-addition trigonometric identities starting from a known value (such as sin(π/2) = 1, cos(π/2) = 0). In modern form, the identities he derived are stated as follows (with signs determined by the quadrant in which x lies): The commonly used trigonometry angles are 0°, 30°, 45°, 60° and 90°. Here is the list of formulas for trigonometry. Therefore, we can write the trigonometry ratios as; The Trigonometric formulas or Identities are the equations which are true in the case of Right-Angled Triangles. In the same way, we can find the trigonometric ratio values for angles beyond 90 degrees, such as 180°, 270° and 360°. Students can refer to the formulas provided below or can also download the trigonometric formulas pdf that is provided above. There are basically 6 ratios used for finding the elements in Trigonometry. Trig Cheat Sheet Definition of the Trig Functions Right triangle definition For this definition we assume that 0 2 p <