In this lesson we discuss the differences in the sign and values of sine, cosine and tangent theta in the four quadrants. Quadrant 1 is from 0 to 90 degrees, quadrant 2 is between 90 to 180, quadrant 3 is between 180 to 270 degrees and quadrant 4 is between 270 to 360 degrees. Remember 360 degrees is the same as 0 degrees (a whole revolution brings us back to the original point).