The Elements of Spherical Trigonometry

a+b+c a+b-c adjacent angle agrees with equation bcos called circle circumference comp cos b cos cos C sin cos² cosines cot a cot cot BC cot² disjoined extremes conjunct extremes disjunct find the angle find the hypothenuse formula Given the side Given the three greater than 90 hence hexahedron hypothenuse BC less than 90 log cos log cot log sin log sin AC middle Napier's Analogies oblique angles opposite angles perpendicular plane angles Plane Trigonometry polar triangle pole polygon QUADRANTAL TRIANGLES radius regular polyhedron right-angled spherical triangle right-angled triangle side AC sin a sin sin c cos sin sin sin sin² a sin² sines six right solid angle sphere spherical triangle SPHERICAL TRIGONOMETRY surface taking the complements tanc three angles three circular three sides triangle ABC triangle is equal