The unit circle is a circle with radius 1, centered at the origin of the coordinate plane. It is a fundamental tool in trigonometry, used to define the trigonometric functions and to solve a wide variety of problems. There are several different ways to memorize the unit circle, each with its own advantages and disadvantages. Some popular methods include:
One common method is to use the mnemonic SOH CAH TOA, which stands for sine, opposite, hypotenuse, cosine, adjacent, hypotenuse, and tangent, opposite, adjacent. This mnemonic can be used to remember the definitions of the trigonometric functions, as well as the values of the trigonometric functions for the special angles 0, 30, 45, and 60. There are countless online resources demonstrating how to use this method.
