CK-12 Foundation
Ck 12: Trigonometry: Conversion Between Degrees and Radians
[Free Registration/Login may be required to access all resource tools.] This lesson introduces the unit circle and radians.
CK-12 Foundation
Ck 12: Determination of Unknown Angles Using Law of Cosines
[Free Registration/Login may be required to access all resource tools.] This lesson covers using the Law of Cosines to find an angle in a triangle.
CK-12 Foundation
Ck 12: Geometry: Arcs and Angles Study Guide
This study guide on arcs and angles covers key vocabulary, arc measurement in degrees and radians, congruent arcs, bisecting arcs, and the angles on, inside, and outside a circle. Also covers formulas and theorems. It is available for...
National Council of Teachers of Mathematics
Nctm: Illuminations: Pi Fight
Become comfortable with using both radians and degrees.
Math Open Reference
Math Open Reference: Angle
Learn about angles with this helpful reference tool. Provides a detailed definition, examples, and an interactive activity that enhances further explanation. Includes links to related topics.
Math Open Reference
Math Open Reference: Arc Length
Learn about arc length with this handy reference guide. Provides a detailed definition examples, and an interactive activity that enhances further explanation. Includes links to related topics.
CK-12 Foundation
Ck 12: Algebra Ii: 4.3 the Unit Circle
Activities in this lesson explore how to identify the coordinates where special right triangles intersect with the unit circle in all four quadrants, use both degrees and radians to identify angles, and explore angles of different sizes...
Khan Academy
Khan: Lesson 16: Part 2 Coordinate Geometry; Trigo and Radians; Complex Numbers
2 OF 2 FOR ADDITIONAL TOPICS IN MATH. Students will use the coordinate plane and equations of lines and circles to describe figures; create the equation of a circle given the figure or use the structure of a given equation to determine a...
Purple Math
Purplemath: Solving Simple (To Medium Hard) Trig Equations
Introduces techniques for solving trigonometric equations. Provides worked examples of solving some simpler to medium-hard equations.
Math2
Math2.org: Trigonometry Tables
Three trig tables are provided for student and teacher reference. The first table lists the sine, cosine, tangent, secant, cosecant, and cotangent values of all whole-number angles from 0 to 90. The radian equivalent (to four decimals)...
ClassFlow
Class Flow: Trigonometric Equations With Multiple Angles
[Free Registration/Login Required] Students will use a number of strategies (including Algebra II and properties of conjunction techniques) to find all solutions for trigonometric equations using multiple angles.
Interactive Mathematics
Interactive Mathematics: Radians
Learn the definition of radians and how to calculate trig ratios using radian measures. Examples are provided showing how to convert from degrees to radians.
Interactive Mathematics
Interactive Mathematics: Angles Degrees and Radians
Angles are key to Trigonometry. Learn definitions of the parts of an angle, degrees, and radians, identify the standard position of an angle, convert between radians and degrees, and more.
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.
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.
Interactive Mathematics
Interactive Mathematics: Applications of Radian Measure
After demonstrating how to find arc length and sector area using radian measures, student can practice the concepts with the examples provided and play an interactive game involving angular velocity.