This account of the theory of the circular functions and their appli-cations to plane trigonometry will provide invaluable assistance to tudents of mathematics who intend to proceed further in the study of analysis. Other students, too, will benefit from the depth with which the more elementary parts of the subject are treated.
Starting with the measurement of angular magnitude and of lines,the text proceeds to discussions of circular functions, including those of two or more angles and of submultiple angles; various the-orems; the expansion of functions of multiple angles; and relations be...