Spherical Trigonometry, for Colleges and Secondary Schools

ABC Fig accordingly altitude ambiguous astronomy axis celestial sphere centre circle passing circumscribing circle compute cos² deduced Delambre's Analogies denote derived described in Art diedral earth earth's surface ecliptic equal equator EXAMPLES face angles find the area formulas frustum geometry Hence horizon hour angle inscribed circle intersection latitude law of cosines law of sines logarithms longitude lune of angle means of right meridian miles Napier's Analogies Napier's rules NOTE number of degrees perpendicular plane triangle Plane Trigonometry polar triangle polyedron radians radii relations respectively right angles right ascension right spherical triangle right triangles right-angled triangle semicircle Show sides and angles sin b sin solid angle solution Solve ABC Solve the polar Solve the triangle sphere of radius spherical degree measure spherical excess spherical measure spherical polygon spherical triangle ABC spherical trigonometry star subtended sun's declination three angles triedral angle zenith