Sine, Cosine and Tangent in the Four Quadrants
Remember this picture? We used it to remember the signs of the three primary trigonometry ratios – Sine, Cosine and Tangent in the four quadrants. Each letter (of ASTC or CAST) represents the trigonometry function that is positive in each quadrant, e.g. Cosine is positive in the 4th quadrant etc., and All three are positive …