Modern college algebra and trigonometry / Edwin F. Beckenbach, Irving Drooyan. Beckenbach, Edwin F. Drooyan, Irving, joint author. Algebra. Plane trigonometry. QA154.2 .B43 1977 512.13 19 BEM Includes index. Belmont, Calif. : Wadsworth Pub. Co., c1977. c1977. 1977 Text 486 p. : eng