Dokaž, že platí \( \large \sin x = \cos \left( x - \Large \frac{\pi}{2}\large \right) \).
\( \large \cos \left( x - \Large \frac{\pi}{2}\large \right) = \sin x \)
\( \large \sin \left( x - \Large \frac{\pi}{2}\large \right) = \cos x \)
\( \large \cos \left( x - \Large \frac{\pi}{4}\large \right) = \sin x \)
\( \large \cos \left( x + \Large \frac{\pi}{2}\large \right) = \sin x \)