Sign of Trigonometric Functions In trigonometry, there are six functions, namely sin, cos, tan, cosec, sec and tan. We can determine the sign of the trigonometric function with the help of a unit circle. Let P (a, b) be a point on the unit circle
Signs of Trigonometric Functions in Each Quadrant We know that cos α = x/r. Since r > 0, the sign of the cosine function depends only on the sign of x. Therefore, the cosine is positive in the 1st