Curated OER
Half Angle
High schoolers calculate the solution using half angles formulas. In this calculus lesson, students identify the different properties of a triangle using trigonometric properties. They identify the mean, altitude and angles of a triangle.
Massachusetts Institute of Technology
Mit: Useful Trigonometric Identities
This list of trigonometric identities includes the factoring formulas near the bottom. A great tool for reference.
Oswego City School District
Regents Exam Prep: Angle Sum & Difference, Double Angle
The mathematics session examines angle sum, angle difference, double angle, and half angle formulas. The tutorial includes class notes, examples, and practice problems with solutions. The teacher resource investigates how the formulas...
Wolfram Research
Wolfram Math World: Half Angle Formulas
This page, from Eric Weisstein's comprehensive Math World site, offers information on half-angle formulas. The site includes traditional trigonometric fuctions half-angle formulas as well as hyperbolic half-angle formulas. Includes links...
CK-12 Foundation
Ck 12: Trigonometric Equations Using Half Angle Formulas
[Free Registration/Login may be required to access all resource tools.] Here you'll learn how to solve trigonometric equations using the half angle formulas.
CK-12 Foundation
Ck 12: Trigonometry: Half Angle Formulas
[Free Registration/Login may be required to access all resource tools.] Using identities to derive more half angle formulas.