Let P=(x,y) be a point on the unit circle and let θ be the corresponding angle . Since the angle θ and θ+2π correspond to the same point P, the values of the trigonometric function...Let P=(x,y) be a point on the unit circle and let θ be the corresponding angle . Since the angle θ and θ+2π correspond to the same point P, the values of the trigonometric functions at θ and at θ+2π are the same.