Download and open circle.html to explore an interactive unit circle. Drag the point around the edge of the circle to change the angle and interact with the unit circle. Special angles (30°, 45°, 60°) ...

In the study of circular functions, the unit circle plays a central role in linking angles with trigonometric values. By defining sine, cosine, and tangent in terms of coordinates on a circle of ...

Not sure, where else should I post my question/doubt. In trigonometry we use the Unit circle: 90 degrees - Pi/2 on the top, and 270 degrees = 3Pi/2. (quick reference ...