Question
If $f(x) = \sin([\pi^2]x) + \cos([-\pi^2]x)$, then $f'(x)$ is, where $[\pi^2]$ and $[-\pi^2]$ denote the greatest integer function, which returns the largest integer not greater than its value.
If $f(x) = \sin([\pi^2]x) + \cos([-\pi^2]x)$, then $f'(x)$ is, where $[\pi^2]$ and $[-\pi^2]$ denote the greatest integer function, which returns the largest integer not greater than its value.