An Elementary Treatise on Trilinear Co-ordinates

AN ELEMENTARY TREATISE

. TRILINEAR CO-ORDINATES,

THE METHOD OF RECIPROCAL POLARS,
AND THE THEORY OF PROJECTIONS.

BY THE REV.

N. M. FERRERS, M.A.

FELLOW AND TUTOR OF GONVILLE AND CAIUS COLLEGE.

UNIVERSITY
OF

CALIFORNIA

THIRD EDITION.

London:

MACMILLAN AND CO.

1876.

Cambridge:

PRINTED BY C. J. CLAY, M.A.

AT THE UNIVERSITY PRESS.

1276

다

PREFACE.

THE prominence which the modern geometrical methods have recently acquired in the studies of the University of Cambridge, appears to justify the publication of a treatise devoted exclusively to these branches of Mathematics. This remark applies more especially to the method of Trilinear Co-ordinates, which forms the subject of the greater part of the following work. My object in writing on this subject has mainly been to place it on a basis altogether independent of the ordinary Cartesian system, instead of regarding it as only a special form of Abridged Notation.

A desire not unduly to increase the size of the book has prevented me from proceeding beyond Curves of the Second Degree.

In this Second Edition several new articles have been

added, especially in the latter part of the work, and the chapter on Reciprocal Polars considerably enlarged.

GONVILLE AND CAIUS COLLEGE,
August, 1866.

N. M. F.

In the Third Edition, I have rewritten some articles where the demonstrations were imperfect or obscure, and have added some examples, taken from various Cambridge Examination papers.

DECEMBER, 1875.