basic trig question (1 Viewer)

[turtle67]

Hi Guys,

In the screenshot I've attached (from my textbook), how is that 100 degree angle as well as that -40, 320 degree angle possible? I would have thought they would be around 350 and 100 respectively?

Sorry if I'm missing something really obvious

 

[shashysha]

The unit circle starts from the x-axis and goes counterclockwise instead of clockwise from the y-axis which you learn while doing bearings and such in junior years. So 100 degrees would be 100 degrees counter clockwise from the x-axis and so on.

 

[turtle67]

The unit circle starts from the x-axis and goes counterclockwise instead of clockwise from the y-axis which you learn while doing bearings and such in junior years. So 100 degrees would be 100 degrees counter clockwise from the x-axis and so on.

ohhhhh true hahaha yeah sorry thank you very much