\begin{eqnarray*}
\sin\left(\frac{\pi}{2}-\theta\right) & = & \cos\theta\\
\cos\left(\frac{\pi}{2}-\theta\right) & = & \sin\theta\\
\tan\left(\frac{\pi}{2}-\theta\right) & = & \cot\theta\\
\cot\left(\frac{\pi}{2}-\theta\right) & = & \tan\theta\\
\csc\left(\frac{\pi}{2}-\theta\right) & = & \sec\theta\\
\sec\left(\frac{\pi}{2}-\theta\right) & = & \csc\theta
\end{eqnarray*}