REA’s EXAM Notes™ are double-sided, laminated reference charts that contain all the information students need on a single reference card. They are colorful and exceptionally well-organized to simplify and speed study. The most often used and required facts and formulas are included. EXAM Notes function as study tools, homework aids, for reference at work. Trigonometric Functions EXAM Notes cover the functions of a right triangle, relations among the functions, angle-sum and angle-difference relations, half-angle relations, relationships between sides and angles of a plane triangle, properties and graphs of trigonometric functions.