Trigonometric ratios and the unit circle

Question

How is the unit circle and the trigonometric ratios related? What happens when the point on the unit circle is in quadrant 1 compared to when the point on the circle is in quadrant 2.

Answer 1

On the unit circle, the points listed as (x,y) correspond to (cos,sin) If you use that along with tan = sin/cos, you can calculate those trig ratios. You can take the reciprocals of each to get csc, sec and cot.

Comparing quadrant 1 and 2, the x coordinates will all be negative. This means that sin will be positive and cos and tan will be negative.