Date: Nov 18, 2013 9:07 AM
Author: Narasimham
Subject: Re: Locus for ratio of cosine of angles to be constant

Typos..

dr/ds - dx/ds ecc = 0 which integrates to

r - x ecc = r - r cos(th) ecc = p, an arbitrary constant.

1 - ecc cos(th) = p/r the polar equation of all conics.

Given constant is eccentricity and arbitrary constant
p is semi-latus rectum.

http://i43.tinypic.com/2med8x4.jpg

Regards
Narasimham