Page images
PDF
EPUB

A TREATISE

OF

PLANE TRIGONOMETRY. .

TO WHICH IS PREFIXED,

A SUMMARY VIEW OF THE NATURE AND USE OF

LOGARITHMS.

BEING

THE SECOND PART

OT

A COURSE OF MATHEMATICS

ADAPTED TO THE METHOD OF INSTRUCTION

IN THE AMERICAN COLLEGES.

BY JEREMIAH DAY,
Professor of Mathematics and Natural Philosophy, in

Yale College.

NEW-HAVEN,

PUBLISHED BY HOWE & DEFOREST.

OLIVER STEELE, PRINTER.

1815.

PUBLIC LIBRARY

150806

ASTOF, LENOX AND
TILDEN FOUNDATIONS.

1899

DISTRICT OF CONNECTICUT, ss.

SEAL.

BE

E IT REMEMBERED; That on

the fifteenth day of May, in the thirtyninth

year of the Independence of the United States of America, JEREMIAH DAY, of the said District, hath deposited in this Office, the title of a Book, the right whereof he claims as Author, in the words following, to wit: "A Treatise of Plane Trigonometry: to which is prefixed, a summary view of the nature and use of Logarithms. Being the Second Part of a Course of Mathematics, adapted to the method of instruction in the American Colleges. By Jeremiah Day, Professor of Mathematics, and Natural Philosophy, in Yale College;" in conformity to the act of the Congress of the United States, entitled, “ An Act for the encouragement of learning, by securing the copies of Maps, Charts and Books, to the authors and proprietors of such copies, during the times therein mentioned.” HENRY W. EDWARDS, Clerk of the

District of Connecticui. A true copy of Record, examined and sealed by me,

H. W. EDWARDS, Clerk of the

District of Connecticut.

THE plan upon which this

work was originally commenced, is continued in this second part of the course.

As the single object is to provide for a class in college, such matter as is not embraced by this design is excluded; with the exception of a few things in the notes. The mode of treating the subjects, for the reasons mentioned in the preface to Algebra, is, in a considerable degree, diffuse. It was thought better to err on this extreme, Ihan on the other, especially in the early part of the course. A more concise method may be adopted in the succeeding numbers.

The section on right angled triangles will probably be 'considered as needlessly minute. The solutions might, in all cases, be effected by the theorems which are given for oblique angled triangles. But the applications of rectangular trigonometry are so numerous, in navigation, surveying, astronomy, &c. that it was deemed important, to render familiar the various methods of stating the relations of the sides and angles; and especially to bring distinctly into view the principle on which most trigonometrical calculations are founded, the proportion between the parts of the given triangle, and a similar one for ned from the sines, tangents, &c. in the tables.

The solutions of oblique angled triangles are made by the common methods. The propositions which are used in particular cases, principally by astronomers, are inserted in a note at the end. On the subject of Trigonometrical Analysis, nothing more than a few of the first principles could be admitted, in a work upon so limited a plan.

This number begins with a view of the nature and use of Logarithms, as preparatory to the calculations in Trigonometry.

« PreviousContinue »