Plane trigonometry, and its application to mensuration and land surveying. Accompanied with all the necessary logarithmic and trigonometric tables (1852)
Perkins, George R. (George Roberts), 1812-1876 · New York, D. Appleton · leaf 16
quotient be-comes CiDi, since the divisor is theradius of the circle, and therefore(§ 5) equal to unity. In the sameway it may be shown that C2D2 isthe sine of the angle C0AC2, thatC4D4 is the sine of the angle C0AC4.As the arc is the measure of angles,we say that C^, C2D2, C4D4, arerespectively… … TRIGONOMETRY. [CHAP. I. In all these cases we suppose the arc to be estimated fromthe point C0, at the extreme right of the circle, upwards andaround towards the left. When angles are estimated from C0downwards around towards the left, they are considered as neg-ative arcs. Thus, C0AC8 is…
Plane trigonometry · Surveying
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