
Also TryLesson Plans
 Math Lessons (Awesome Library)
Provides lessons, worksheets, and activities. 600
Lists
 Trigonometry (Math Forum)
Provides sources of lessons.
 Trigonometry  Basic Course (Clark University  Joyce)
Provides explanations, diagrams, problems, and answers for basic trigonometry concepts and problems. 400
 Trigonometry  Solving Right Triangles (Clark University  Joyce)
Provides an explanation and problems for solving right triangles. Includes answers. 400
Papers
 Trigonometry Resources (Fife and Husch)
Provides nearly three dozen sources on trigonometry. 500
 Spherical Trigonometry (University of Cambridge  Eagleton)
"One of the primary concerns in astronomy throughout history was the positioning of the heavenly bodies, for which spherical trigonometry was required. The diagrams below show trihedrals, polyhedra with triangular sides. For astronomy, V is the position of the observer, and PQR are points on a sphere centred at V, the celestial sphere."
 Trigonometry (Wikipedia.org)
"Trigonometry (Greek: 'the measure of triangles') is a branch of mathematics dealing with angles, triangles and trigonometric functions such as sine and cosine. It has some relationship to geometry, though there is disagreement on exactly what that relationship is; for some, trigonometry is just a subtopic of geometry."
Includes Angle, Angle excess, Gudermannian function, Law of cosines, Law of sines, Law of tangents, List of trigonometry topics, Radian, Spherical trigonometry, Tangent halfangle formula, Trigonometric function, Trigonometric identity, Trigonometric rational function, Uses of trigonometry, and Versine.
 Trigonometry (Zobel)
Provides definitions and graphs of trigonomic functions. Includes an animation of sin(x).
 Trigonometry  Formulas for Triangles (Levy)
Provides formulas and diagrams for triangles.
 Trigonometry  More Advanced (S.O.S. Mathematics)
Provides problems and solutions.
 Trigonometry Basics (Kelly)
Provides an introduction and formulas for solving basic trigonometry problems. Includes Definitions and basics, Trigonometric circle and angles, Trigonometric numbers of a real number t, Basic formulas, Related values, Supplementary values, Complementary values, Opposite values, Anti supplementary values, The rightangled triangle, Area of a triangle, Sine rule, Homogeneous expression in a, b and c, Cosine rule, Trigonometric functions, The sine function, The cosine function, The tangent function, The cotangent function, Inverse Trigonometric Functions, The arcsin function, The arccos function, The arctan function, The arccot function, Sum formulas, cos(u  v), cos(u + v), sin(u  v), sin(u + v), tan(u + v), tan(u  v), sin(2u), cos(2u), tan(2u), Carnot formulas, tformulas, Special values, pi/3, pi/4, pi/6, Trigonometric equations, Base equations, cos(u) = cos(v), sin(u) = sin(v), tan(u) = tan(v), cot(u) = cot(v), Reducing to base equations, Using an additional unknown, Using factorization, The equation a.sin(u)+b.cos(u) = c, Homogeneous equations, and Calculations with inverse trigonometric functions.
 Trigonometry Basics  Problems and Solutions (WebMath)
Provides solutions and answers to basic problems in trigonometry, including Right Angle Relationships, Graphing Trig Functions, Simplifying Trig Functions, and Polar Graphs.
 Trigonometry Explained (Columbia Encyclopedia)
Explains the basics of trigonometry for advanced students.
 Trigonometry Explained (Columbia Encyclopedia)
Explains the basics of trigonometry for advanced students.
 Trigonometry Functions  History (University of St. Andrews, Scotland)
Provides a history of trigonometry functions and the mathematicians behind their discovery.

