 The problem therefore is reduced to finding the centre of a circle to touch externally two given circles (DG, EG) and pass through a given point (Q), which is always possible since the circles must cut each other and Q lie outside both, ie the problem...  Constructive geometry of plane curves - Page 125by Thomas Henry Eagles - 1885Full view - About this book
 | Encyclopedias and dictionaries - 1910 - 1098 pages
...the focus and directrix from the ci'ir rv; and 3«>SP^-S'P,.irh<r« P is any pcfifit on the cun^e, ir the sum of the focal distances of any point on the curve cuoaU the major,ajtj«. ITJie most important relation between the co-ordinates of a p' im on an etmrtc... | |
 | Hugh Chisholm - Encyclopedias and dictionaries - 1910 - 1012 pages
...the focus and directrix from the centre : and за -SI'+S'P, where P is any point on the curve, ie the sum of the focal distances of any point on the curve equals the major axis. The most important relation between the co-ordinates of a point on an ellipse... | |
 | Henry John Spooner - Geometrical drawing - 1911 - 196 pages
...traced will be a quadrant of a circle, GBF. i You will understand this expedient when you remember that the sum of the focal distances of any point on the curve is always equal to the major axis. (Fig. 212) FD + FZD = AB. This is important, and should not be forgotten.... | |
 | Derrick Norman Lehmer - Geometry, Projective - 1917 - 146 pages
...directrices. In the hyperbola this distance is (d — d ' ). It follows (Fig. 48) that In the ellipse the sum of the focal distances of any point on the curve is constant, and in the hyperbola the difference between the focal distances is constant. PROBLEMS... | |
 | Clyde Elton Love - Geometry, Analytic - 1927 - 288 pages
...definition is equivalent to the one already given, we must prove that, for the ellipse as formerly defined, the sum of the focal distances of any point on the curve is constant, and that this property is possessed by no FIG. 83 other curve. Let P : (x, y) be any point... | |
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