Resources

Adamek, T., Penkalski, K., & Valentine, G. (2005). The history of trigonometry. History of Mathematics, 11.

Calter, P. (2000). Facade measurement by trigonometry. 20-25.

Gonzala, S. (n.d.). Retrieved from https://www.alamo.edu/contentassets/35e1aad11a064ee2ae161ba2ae3b2559/analytic/math2412-double-angle-power-reducing-half-angle-identities.pdf

Gutmann, T. (2003). A Direct Approach to Computing the Sine or Cosine of the Sum of Two angles. The Mathematics Teacher, 314-318.

Jarrett, J.A. (1987). A Geometric Proof of the Sum-Product Identity for Trigonometric Functions. The Mathematics Teacher, 240-244.

Joyce, D.E. (1997). Summary of trigonometric identities. Retrieved from Dave's Short Trig Course:https://www2.clarku.edu/faculty/djoyce/trig/identities.html.

L,H.[Hannah L.].(2017,Oct 30).Real Life Applications of Trigonometric Identities[video]. YouTube. https://www.youtube.com/watch?v=cMnMxTEt9dM.

Massa,M.R., Romero, F., & Guevara, I. (2006). Teaching mathematics through history: Some trigonometric concepts. Proceedings of the Second International Conference of the European Society for the History of Science. Cracow.

Moore, K.C., & LaForest, K.R. (2014). The Circle Approach to Trigonometry. The Mathematics Teacher,616-623.

Murphy, R.D. (1998). An historic-geometric developmsent of trigonometric concepts.Southern Connectticut State University, 18-23.

Quinn, C.M., Smith, D.K., Chappell, M.F., Carver, S.D., Duffy, S., Holcomb Jr, J.P.,...Resnick, A. (2017). Music as math waves:exploring trigonometry through sound. Journal of Mathematics and the Arts, 173-184.

Rogers, L. (2010). History of Trigonometry - Part 3. Retrieved from NRICH: https://nrich.maths.org/6908.

Rule, S. D. (2006). Trigonometry Saves Engineer's Time. The Mathematics Teacher, 484-486.

Salingaros, N.A.(1999). Architecture, Patterns, and Mathematics. Nexus network journal,75-86

Cazelais, G. (2006, June 12). Proof of Sum and Difference Idenitites. Retrieved from https://mymission.lamission.edu/userdata/sargsye2/docs/Math%20240/Proof%20of%20the%20difference%20formula%20for%20cosine.pdf

Real life applications of trigonometry. (2017, Oct 16.). Retrieved from Mathnasium:https://www.mathnasium.com/real-life-applications-of-trigonometry