When working in Quadrant I, things make sense to me. Angles are bound between 0 and 90 degrees and we can talk about sin, cos, and tan in terms of ratios of sides of triangles.
But when we increase the angle and start moving into other quadrants I no longer understand how you're supposed to interpret things. I'll see someone draw a triangle in Quadrant III like normal but then somehow it's still reconciling with this huge angle that's sprawling all the way over from 0 on the unit circle.
How am I supposed to interpret these trigonometric functions in other quadrants?