Lawrence Hall of Science
The Math Page: Trigonometry: Inverse Trigonometric Function
Here is a site that clearly and thoroughly explains each of the six inverse trigonometric functions. There are example problems solved, problems for the student to attempt, and answers to the student problems. Point this site out to...
Other
Karl's Calculus Tutor: Derivative of Inv. Trig Functions
This site provides a general overview of the derivative of inverse trig trunctions. Content includes a proof, exercises, and more.
Northeast Parallel Architectures Center, Syracuse University
Npac Reu Program: Sign (+ or ) of the Trig Functions
Northeast Parallel Architectures Center of Syracuse University provides a quick overview of the signs of the six trigonometric functions in the four quadrants of the coordinate plane.
Varsity Tutors 
Varsity Tutors: Hotmath: Algebra Review: Trigonometric Ratios
Find a quick, concise explanation of the trigonometric ratios: sine, cosine and tangent. Examples are given and clearly explained.
Khan Academy
Khan Academy: Find Trig Values Using Angle Addition Identities
Find the trigonometric values of various angles that (while they are not special angles) can be expressed as the sum or difference of special angles. Students receive immediate feedback and have the opportunity to try questions...
Illustrative Mathematics
Illustrative Mathematics: F Tf Trig Functions and the Unit Circle
The purpose of this task is to help students make the connection between the graphs of sin t and cos t and the x and y coordinates of points moving around the unit circle. Students have to match coordinates of points on the graph with...
CK-12 Foundation
Ck 12: Trigonometry: Composition of Inverse Reciprocal Trig Functions
[Free Registration/Login may be required to access all resource tools.] Define inverse reciprocal of trigonometric functions.
CK-12 Foundation
Ck 12: Trigonometry: Applications of Inverse Trigonometric Functions
[Free Registration/Login may be required to access all resource tools.] Here you'll learn how to apply inverse trig functions to solve problems you would see in real-life situations.
CK-12 Foundation
Ck 12: Trigonometry: Trigonometric Functions and Angles of Rotation
[Free Registration/Login may be required to access all resource tools.] Describing trig functions as relationships on the unit circle.
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.
Curated OER
Zona Land: Overlapped Graph of the Six Trig Functions
An overview of the six trig functions and their graphs. The site is a little difficult to navigate but is good for finding a graph of a trig function.
Calculator Soup
Calculator Soup: Inverse Trigonometric Function Graphs
Shows images of inverse trigonometric function graphs.
Calculator Soup
Calculator Soup: Trigonometric Function Graphs F(x)
Images of trigonometric function graphs.
Government of Alberta
Learn Alberta: Math Interactives: Exploring Trigonometry (Video Interactive)
This multimedia Learn Alberta math resource looks at how trigonometry is used in making sure that airplanes land safely at airports. The accompanying interactive component gives students practice in using trigonometric ratios, namely...
University of California
Uc Davis: Trigonometric Integrals
This site lists numerous trigonometric identities and integrals. It also provides several examples of how to solve integrals.
CK-12 Foundation
Ck 12: Trigonometry: Definition of Inverse Reciprocal Trig Functions
[Free Registration/Login may be required to access all resource tools.] Define reciprocal function.
Other
Karl's Calculus Tutor: Trigonometric Functions
Great application of trig and introduction to the trig functions. Also found here are the Law of Sines and Law of Cosines as well as other trig topics to review.
Khan Academy
Khan Academy: Intro to Inverse Trig Functions
Learn about arcsine, arccosine, and arctangent, and how they can be used to solve for a missing angle in right triangles.
Texas Instruments
Texas Instruments: Math Today When a Ruler Isn't Enough
This activity illustrates a real-life problem that uses trigonometry to solve for an unknown. students can use trigonometric ratios and inverse trigonometric relationships to determine the side of a triangle and the measure of the...
Texas Instruments
Texas Instruments: Real Life Real World Activity Forestry
Forest industry professionals make measurements in their work using tools including the Clinometer and the Biltmore Stick. These tools are based on the concepts of similar triangles and trigonometric ratios in a right triangle. This...
Windstream
Ojk's Precalculus Study Page: Sum and Difference Formulas for Sine and Cosine
An introduction to trigonometric identities, beginning with the sum and difference formulas. Some of the formulas are proven, some are left to the reader. Includes several examples and pictures.
Illustrative Mathematics
Illustrative Mathematics: G C, G Srt Setting Up Sprinklers
In this task, students must decide where to place sprinklers on a lawn so that the maximum area of the lawn will be watered. To solve it, they must find areas of sectors of circles and use trigonometric ratios to solve right triangles....
CK-12 Foundation
Ck 12: Trigonometric Functions of Angles Greater Than 360 Degrees
[Free Registration/Login may be required to access all resource tools.] Finding the value for trigonometric functions for angles exceeding 360 degrees.
CK-12 Foundation
Ck 12: Trigonometry: Trigonometric Functions of Negative Angles
[Free Registration/Login may be required to access all resource tools.] Learn how to define trigonometric functions of angles with negative values.