Elements of plane and spherical trigonometry

altitude angled spherical triangle axis azimuth base becomes bisect centre chap chord circle of latitude computation consequently cos2 COSB cosec cosine cotangent declination deduced determine dial diameter difference draw earth ecliptic equa equal equation Example expression find the rest formulae given side gonal half Hence horizon hour angle hypoth hypothenuse inclination intersecting latitude logarithmic longitude measured meridian method obliq oblique observed opposite angle parallel perpendicular plane angles plane triangle pole preceding problem prop quadrant radius rectangle respectively right angled spherical right angled triangle right ascension right line secant sin2 sine sines and cosines solid angle sphere spherical excess spherical trigonometry star substyle sun's supposed surface tan2 tangent theorem three angles three sides tion triangle ABC versed sine versin vertical angle whence