I take it you're asking this because of 3 main things:
Peoples sometimes include radians when they write angles inside of cos e.g. ##\cos( \pi/3 \ rad )## but sometimes it's omitted because rad is conventionally considered to be unitless
I've just redefined rad to be i instead of unitless...
I know this is an older thread, but I have a thought regarding this.
At every point, the circumference of a circle is perpendicular to the radius vector between the point on the circumference and the center of the circle. When you say an angle is the ratio between a given arc segment of the...