Purple Math
Purplemath: Inverses of Trigonometric Ratios
You know that you can take side lengths and find trig ratios, and you know you can find trig ratios (in your calculator) for angles. What is missing is a way to go from the ratios back to the original angles. And that is what "inverse...
Khan Academy
Khan Academy: Solve for an Angle in Right Triangles
Given two sides in a right triangle, find one of the acute angles using trigonometry. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Solve for a Side in Right Triangles
Given one side length and an acute angle in a right triangle, find another side using trigonometry. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Razones Trigonometricas
In Spanish. In this interactive activity you will learn about the six trigonometric ratios, discover relationships between the trigonometric ratios of complementary and supplementary angles and the relationship between the sides of a...
Windstream
Ojk's Pre Calculus Study Page: The Four Other Trig Functions
Trigonometry ratios and their signs are given in this explanation of the other trig functions. Graphs of tangent, cotangent, secant, and cosecant are given. Examples are included.
CK-12 Foundation
Ck 12: Exact Values for Inverse Sine, Cosine, and Tangent
[Free Registration/Login may be required to access all resource tools.] Find all angles on the unit circle matching exact trig ratios. Resource includes examples, videos, and practice problems.
CK-12 Foundation
Ck 12: Definition of the Inverse of Trigonometric Ratios
[Free Registration/Login may be required to access all resource tools.] Explain the inverse of trigonometric functions.
Government of Alberta
Learn Alberta: Exploring Similarity and Congruence
Begin by watching this captivating video showing how the concepts of similarity and congruence are found in road signs. Following the video [1:27], an interactive applet allows students to resize, flip, move and rotate triangles to...
Texas Instruments
Texas Instruments: Investigating Special Trangles
This activity will help students visualize the construction of these special triangles and find the ratios of the sides. It will help students later when they being trigonometry. [Requires Adobe Reader.]
Math Words
Math words.com: Trig Identities
This MathWords.com site lists the equations for all of the trigonometric identities.