1. The problem statement, all variables and given/known data Is f(x) = cos^2(x) + sin^2(x) a periodic function? 2. Relevant equations sin^2(x) + cos^2(x) = 1 3. The attempt at a solution This question is just something that randomly came to my mind (not a hw problem). I know cos^2(x) and sin^2(x) are both periodic functions, but is sin^2(x) + cos^2(x) a periodic function too? If so, what would be its fundamental frequency?