In the absolute path in space
cos [psi] = (2 - 3 sin² [theta])/[root](4 - sin² [theta]),
and sin³ [theta] = (y³ - c²y)/a³, (19)
which leads to no simple relation.
Encyclopaedia Britannica, 11th Edition, "Hydromechanics" to "Ichnography" Volume 14, Slice 2 · 第 40 / 120 题