Trigonometric Terms

Section 4.1

Trigonometric Terms

Rotating a ray about its axis determines an angle.
The starting position of a ray is initial side of an angle. The position of the ray after rotation is called the terminal side. The endpoint of a ray is called the vertex of the angle.

An angle in standard position has the vertex at the origin (the point (0, 0)) and the initial side on the x-axis or the line y = 0.



Clockwise rotation of an angle yield negative angles. Counterclockwise rotation of an angle yield positive angles.

When angles have the same initial and terminal sides, they are called coterminal angles.

 

way to go

 

By the way, I took Algebra 2 and Trigonometry back in the late 1980s at NYC Technical College (today NYC College of Technology).