$$\color{rgb(0,127,0)}\frac{\pi }{2 }$$

$$\color{rgb(0,0,255)}\cos \, {\theta }$$

$$\color{rgb(127,0,0)}\sin \, {\theta }$$

$$\color{rgb(127,0,0)}-\sin \, {\theta }$$

$$\color{rgb(0,0,0)}\begin{array}{l} {\displaystyle \cos {\left( {\frac{\pi }{2} + \theta } \right) = -\sin \, \theta } } \\ {\displaystyle \sin {\left( {\frac{\pi }{2} + \theta } \right) = \cos \, \theta } } \end{array}$$

$$\color{rgb(0,0,255)}\theta$$

$$\color{rgb(0,0,255)}\theta$$

$$\color{rgb(255,0,0)}\frac{\pi }{2 } + \theta$$

$$\color{rgb(127,0,127)}\frac{\pi}{2}-\theta$$

$$\color{rgb(0,0,255)}\cos \, {\theta }$$

$$\color{rgb(0,127,127)}-\theta$$

$$\color{rgb(127,0,0)}\sin \theta$$