TR1.2 - Unit Circle - Part I
Channel: MATH 1151
Date: 29/08/2018

The Unit Circle - Part I establishes the connection between angles measured counterclockwise from the positive side of the x-axis and points on a circle of radius 1 and formalizes this as a function from angles to points (ordered pairs). From this, the sin and cos functions are defined. Value of sin θ and cos θ are found for angles which are multiples of 90◦. Values which come from the 30 − 60 − 90 triangle and the 45 − 45 − 90 triangle are presented in the Unit Circle - Part II lesson.