Question

derive napier's and projection formula​

Answer 1

John Napier (1550–1617) discovered a way to reduce 10 equations in spherical trig down to 2 equations and to make them easier to remember. Draw a right triangle on a sphere and label the sides a, b, and c where c is the hypotenuse.

John Napier (1550–1617) discovered a way to reduce 10 equations in spherical trig down to 2 equations and to make them easier to remember. Draw a right triangle on a sphere and label the sides a, b, and c where c is the hypotenuse.a right triangle on a sphere and label the sides p, q, and r where r is the hypotenuse. Let P be the angle opposite side p, Q the angle opposite side q, and R the right angle opposite the hypotenuse r.