What is Cosine Function?

Cosine Function is a trigonometric function taking an angle as input and giving output as the ratio of the length of the side adjacent to the angle and hypotenuse in a right-angled triangle. A cosine function can also be used to represent periodic variations with specific boundary conditions. Periodic variations represented by cosine functions are also called sinusoidal variations.

Domain of a cosine function can also be any real number and the range lies between -1 and 1. But, the cosine function is an even function which implies that the cosine of a negative angle is the same as that of a positive angle with the same magnitude, i.e. cos(-x) = cos(x).

Sine and Cosine Functions are the fundamental aspects that form the basis for Trigonometry. In a general sense, they relate to the ratio of lengths of a right-angled triangle, i.e. sine of an angle is the ratio of the side opposite to the angle the hypotenuse of the triangle and the cosine of an angle is the ratio of the base and hypotenuse of the triangle.

They are used to represent variations of certain physical quantities such as displacement in simple harmonic motion, alternating current, sound waves, etc. Additionally, sine and cosine functions find applications in computer graphics, signal processing, simulation, encryption and decryption, etc.

In this article, we will briefly discuss various real-life applications of sine and cosine functions.