Practical plane and solid geometry for advanced students, including graphic statics, adapted to the requirements of the South Kensington syllabus (1899)
Harrison, Joseph, Baxandall, George Albert · London Macmillan · leaf 120
ces, and AA is the transverse axis. BB, perpendicular to AA, is called the conjugate axis,being determined by the condition that AB = AB = CE= CE = CF. The diagonals DE, DE, produced indefinitely bothways, are asymptotes to the curve. Asymptotes are lines which, as they recede to infinity witha… … Theorem 1.—The difference of the focal radii is constant,and equal to the transverse axis. Observe that in the ellipse it is the sum which is constant. Theorem 2.—The tangent PT at any point P bisects thefocal radii PP, PP. In the ellipse it is the normal which bisects this angle. From any point Q…
