Using Euler’s theorem, geometric sums and Chebyshev polynomials, we prove trigonometric identities involving sums and multiplications of cosine.

Author Bio

Sarah Weller graduated from Colorado Mesa University in 2017 with a Bachelor of Science in mathematics. Her work was done as part of a capstone course as an undergraduate student under the guidance of Markus Reitenbach. She intends to attend graduate school in 2018 to pursue a PhD in mathematics.