798. With respect to which axes are the curves $y=\sin x$ and $y=\cos x$ mutually symmetric?
798. With respect to the parallels to the $y$-axis, corresponding to the abscissas

$$
x=\frac{\pi}{4}, \frac{5}{4} \pi, \frac{9}{4} \pi \ldots,-\frac{\pi}{4},-\frac{5}{4} \pi,-\frac{9}{4} \pi \ldots
$$