수학중독-수학에 미치다

$$\overline {AQ}=\sec \theta -1 $$ $$ g\left( \theta \right) =\dfrac {1} {2}\left( \begin{matrix} \sec \theta-1\end{matrix} \right) ^{2}\cdot \left( \dfrac {\pi } {2}-\theta \right) $$ $$f\left( \theta \right) =\dfrac {1} {2}\sin \theta \cos \theta $$ $$\Rightarrow \dfrac {\left( \begin{matrix} \sec\theta-1\end{matrix} \right) \sqrt {\dfrac {\pi } {4}-\dfrac {\theta } {2}}} {\dfrac {\theta } {2}..