D davidn92 New Member Joined Nov 19, 2009 Messages 3 Gender Male HSC 2010 Mar 4, 2010 #1 Is the focal length of an ellipse the sum of the distances from a point P to the foci (ie, PS + PS' = 2a) or is it the distance between the foci (ie, SS' = 2ae). Reliable sources will be appreciated.
Is the focal length of an ellipse the sum of the distances from a point P to the foci (ie, PS + PS' = 2a) or is it the distance between the foci (ie, SS' = 2ae). Reliable sources will be appreciated.
K kevin101 New Member Joined Dec 7, 2009 Messages 17 Location Sydney Gender Male HSC 2010 Mar 4, 2010 #2 PS + PS' = 2a