Unit Circle Labeled At Quadrantal Angles Small 320×318 Medium 640×636 Large 1024×1018 Download TIFF Original 3017×3000 | (136.9 KB) Download EPS Vector 352.2 KB Description Illustration of a unit circle (circle with a radius of 1) superimposed on the coordinate plane with the x- and y-axes indicated. All quadrantal angles are given in radian measure in terms of pi. Keywords 45°, analytic geometry, circles, coordinate plane, cos, cosecant, cosine, cot, cotangent, csc, Degree, degrees, quadrantal angles, quadrants, radian, radians, radius of 1, ratio, sec, secant, sin, Sine, special angles, Tan, tangent, trig, trig ratios, trigonometric functions, trigonometry, unit circle Galleries Unit Circles Source: Florida Center for Instructional Technology Clipart ETC (Tampa: University of South Florida, 2007)