Analytic geometry and principles of algebra (1913)
Ziwet, Alexander, 1853-1928, Hopkins, Louis Allen, joint author, Hedrick, E. R. (Earle Raymond), 1876-1943 · New York, The Macmillan Company · leaf 242
onstant r^ sin a by jj we have ^ . QC = 4. To sin a =4.2^.OQ The equation of the conic in this case, referred to its axis OQand vertex 0, is therefore f = 4.2^x. Notice that as j^ = o sin a the focus isfound as the foot of the perpendicularfrom the midpoint of OB on OQ. 241. Ellipse. In the second… … Fig. yy CQ _ sin ^ OQ sin(|-7r —«) QC ^ sin(/3-2«)QO sin(i7r-fa) 230 PLANE ANALYTIC GEOMETRY [XI, § 241 whence QP~ ^ sin (i sin ((3-2 a)OQ QO ~ cos2 a an expression independent of the position of the cross-sectionCO. Denoting this positive constant by A-, we find the equation if = kx{2a-x), I.e. a-…
Geometry, Analytic
Internet Archive · Public Domain Mark 1.0. Free to use for anything.
