| Samuel Vince - Astronomia - 1814
...sin. PB = 2 cosec. Pfl = 2 sec. QB; therefore £ DK = sec. QB. Hence, the radius of projection of any **great circle is the secant of the angle between the...the circle and the plane of projection. From these** four articles it appears, that the projection of the parts of the sphere will not properly represent... | |
| Francis Henney Smith - Arithmetic - 1845 - 276 pages
...4. The projection of every great circle passing through the pole is a straight line. 5. The radius **of projection of any other great circle is the secant...parts of the sphere will not properly represent, in** magnitude and situation, the parts themselves. G. If the place of the eye be the pole of the earth,... | |
| Isaac Todhunter - Conic sections - 1874 - 358 pages
...therefore, by Art. 371, the ellipse can be obtained by projection from a circle of radius a; and the cosine **of the angle between the plane of the circle and the plane of** the ellipse is - . The area of the circle is known to be тга2 ; see Trigonometry. Hence, by Art.... | |
| ...minor axis. Since ' OB OB' b D hence : The ratio of the minor axis to the major axis gives the cosine **of the angle between the plane of the circle and the plane of projection.** MM 7 98 [CH. Since the area of the ellipse is equal to the area of the circle multiplied by cos 6,... | |
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