Curves with a directrix ...
Publisher: Scholarly Publishing Office, University of Michigan Library
Published: December 20, 2005
Language: eng
Format: Paperback
Number of pages: 33
ISBN-13: 9781418177461
Subjects: Mathematics / General
First sentence: It is a well-known fact of elementary geometry that the orthocentre of any three lines of a parabola, which is of course uniquely determined by four lines, lies on a line, called the directrix of the parabola.