Relationships In A Spherical Triangle Small 320×309 Medium 640×618 Large 1024×989 Download Tiff Original 2400×2317 | (305.9 KB) Description Illustration used to extend the law of cosines when finding the relation between the three sides and an angle of a spherical triangle. In this case angle b<90° and angle c>90°. Keywords analytic geometry, angle, cosine, sector, spherical triangles, trigonometric, trigonometry Galleries Spheres Source: George N. Bauer, PH.D. and W.E. Brooke, C.E., M.A. Plane And Spherical Trigonometry (Boston: D.C. Heath & Co., 1917) 130 Courtesy the private collection of Roy Winkelman