Definitions (Inverse Trigonomic Functions)

In this lesson, we will learn how to define the inverse of both sine and cosine functions.

Inverse of Sine Function

For the function y = sin x, the inverse function is defined by x = sin^–1y, where –1 ≤ y ≤ 1. This means that x is the function of an angle whose sine equals y. Thus, we can deduce the function y from x and vice versa. For example, if x = sin^–1.45, then sin x = .45, or if sin x = .77 then x = sin^–1.77.