Wolfram Research
Wolfram Math World: Slope
This site from MathWorld.com provides charts, links, and definitions pertaining to slope.
University of Regina (Canada)
Univeristy of Regina: Math Central: Tangent Lines and Circle Equations
This site offers a problem and solution to finding all possible slopes for a line tangent to a circle given a particular equation of a circle. Could be an interesting challenge for students.
Math Medics
S.o.s. Math: Trigonometric Functions
Introductory lesson to trigonometric functions. Includes definitions, properties, graphs, and a wide variety of examples and practice exercises.
Other
Technical Tutoring: The Very Fast Trig Review
This resource is a quick review of the functions and identities in trigonometry.
Other
Trigonometry: A Quick Review
This site is a personal site from David Eisenberg and it contains brief but great review information for trigonometry. This particular site focuses on sine and cosine inlcuding a small circle graph. Clicking on the index link provides...
Other
Technical Tutoring: Trigonometry: The Very Fast Review
This site is a quick review of the functions and identities in trigonometry. Very helpful site.
Other
Gobierno De Navarra: Familias De Funciones Elementales
Visualize the different kinds of functions with these interactive activities.
Other
Technical Tutoring: Trig Identities
This resource is a quick review of the functions and identities in trigonometry.
Mr. Martini's Classroom
Mr. Martini's Classroom: Right Angle Trigonometry
Explore sine, cosine, and tangents compared to the selected angle.
Sophia Learning
Sophia: Trigonometric Values From a Calculator: Lesson 2
This lesson will illustrate how to use a calculator to find the value of a trigonometric value. It is 2 of 5 in the series titled "Trigonometric Values from a Calculator."
Sophia Learning
Sophia: Trigonometric Values From a Calculator: Lesson 5
This lesson will illustrate how to use a calculator to find the value of a trigonometric value. It is 5 of 5 in the series titled "Trigonometric Values from a Calculator."
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.
ClassFlow
Class Flow: Advanced Trigonometry
[Free Registration/Login Required] Students describe, analyze, and reason angles being as small or as large as they can imagine. Using trigonometrical ratios, this is a fun exercise in understanding how to examine the perfect graph.
ClassFlow
Class Flow: Basic Right Triangle Trigonometry
[Free Registration/Login Required] This flipchart shows the basic relationships between trig functions and the sides and angles of a right triangle.
Interactive Mathematics
Interactive Mathematics: Graphs of Tan, Cot, Sec, & Csc
Several examples are presented that demonstrate how to graph the tan, cot, sec, and csc functions.
Interactive Mathematics
Interactive Mathematics: Sine, Cosine, Tan & Reciprocals
The definitions of the six trig ratios are presented here, along with several examples of how to determine the ratios given 2 or more sides of a right triangle.
BBC
Bbc: The Circle
The equation of a circle is the focus of this site. Topics include tangents, intersecting circles, and intersection of lines and circles. Examples and a practice test are available.
Math Planet
Math Planet: Pre Algebra: Trigonometry
Learn about trigonometry by viewing examples and a video lesson.
Other
Lifewire: Excel Tan Function: How to Find the Tangent Angle
This article shows you how to find the tangent angle using Excel. You may be able to accomplish this on a scientific calculator, but if you don't have one handy, Excel can help you make these calculations better than anything else.
Interactive Mathematics
Interactive Mathematics: Trigonometric Functions
This is a excellent review lesson about trigonometric functions of any angle. Good examples here.
Other
Gobierno De Navarra: Trigonometria
Use these interactive activities as a supplementary material to visualize some basic concept of Trigonometry.
Interactive Mathematics
Interactive Mathematics: Trigonometric Functions
Just about everything you need to know about trigonometry can be found here. Interactive examples and demonstrations help to enhance the lessons. Although not required, the tutorial uses Live Math and Scientific Notebook.
Calculator Soup
Calculator Soup: Trigonometric Function Graphs F(x)
Images of trigonometric function graphs.
Calculator Soup
Calculator Soup: Trigonometric Functions Calculator
This online trigonometry calculator will calculate the sine, cosine, tangent, cotangent, secant and cosecant of angle values entered in degrees or radians. The trigonometric functions are also known as the circular functions.