Tenemos la indeterminación de tipo
0/0,
tal que el límite para el numerador es
$$\lim_{x \to \frac{\pi}{2}^+} \frac{1}{\tan{\left(x \right)}} = 0$$
y el límite para el denominador es
$$\lim_{x \to \frac{\pi}{2}^+} \frac{1}{\log{\left(\frac{\pi - 2 x}{2} \right)}} = 0$$
Vamos a probar las derivadas del numerador y denominador hasta eliminar la indeterminación.
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{\log{\left(- x + \frac{\pi}{2} \right)}}{\tan{\left(x \right)}}\right)$$
=
Introducimos una pequeña modificación de la función bajo el signo del límite
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{\log{\left(\frac{\pi - 2 x}{2} \right)}}{\tan{\left(x \right)}}\right)$$
=
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{\frac{d}{d x} \frac{1}{\tan{\left(x \right)}}}{\frac{d}{d x} \frac{1}{\log{\left(\frac{\pi - 2 x}{2} \right)}}}\right)$$
=
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{\left(\pi - 2 x\right) \left(- \tan^{2}{\left(x \right)} - 1\right) \log{\left(- x + \frac{\pi}{2} \right)}^{2}}{2 \tan^{2}{\left(x \right)}}\right)$$
=
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{\frac{d}{d x} \frac{\left(\pi - 2 x\right) \left(- \tan^{2}{\left(x \right)} - 1\right)}{2 \tan^{2}{\left(x \right)}}}{\frac{d}{d x} \frac{1}{\log{\left(- x + \frac{\pi}{2} \right)}^{2}}}\right)$$
=
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{\left(- x + \frac{\pi}{2}\right) \left(\frac{\left(\pi - 2 x\right) \left(- 2 \tan^{2}{\left(x \right)} - 2\right) \left(- \tan^{2}{\left(x \right)} - 1\right)}{2 \tan^{3}{\left(x \right)}} - \frac{\left(\pi - 2 x\right) \left(2 \tan^{2}{\left(x \right)} + 2\right)}{2 \tan{\left(x \right)}} - \frac{- \tan^{2}{\left(x \right)} - 1}{\tan^{2}{\left(x \right)}}\right) \log{\left(- x + \frac{\pi}{2} \right)}^{3}}{2}\right)$$
=
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{\frac{d}{d x} \frac{\left(- x + \frac{\pi}{2}\right) \log{\left(- x + \frac{\pi}{2} \right)}^{3}}{2}}{\frac{d}{d x} \frac{1}{\frac{\left(\pi - 2 x\right) \left(- 2 \tan^{2}{\left(x \right)} - 2\right) \left(- \tan^{2}{\left(x \right)} - 1\right)}{2 \tan^{3}{\left(x \right)}} - \frac{\left(\pi - 2 x\right) \left(2 \tan^{2}{\left(x \right)} + 2\right)}{2 \tan{\left(x \right)}} - \frac{- \tan^{2}{\left(x \right)} - 1}{\tan^{2}{\left(x \right)}}}}\right)$$
=
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{\left(- \frac{\log{\left(- x + \frac{\pi}{2} \right)}^{3}}{2} - \frac{3 \log{\left(- x + \frac{\pi}{2} \right)}^{2}}{2}\right) \left(\frac{\left(\pi - 2 x\right) \left(- 2 \tan^{2}{\left(x \right)} - 2\right) \left(- \tan^{2}{\left(x \right)} - 1\right)}{2 \tan^{3}{\left(x \right)}} - \frac{\left(\pi - 2 x\right) \left(2 \tan^{2}{\left(x \right)} + 2\right)}{2 \tan{\left(x \right)}} - \frac{- \tan^{2}{\left(x \right)} - 1}{\tan^{2}{\left(x \right)}}\right)^{2}}{- \frac{\left(\pi - 2 x\right) \left(- 3 \tan^{2}{\left(x \right)} - 3\right) \left(- 2 \tan^{2}{\left(x \right)} - 2\right) \left(- \tan^{2}{\left(x \right)} - 1\right)}{2 \tan^{4}{\left(x \right)}} + \frac{\left(\pi - 2 x\right) \left(- 2 \tan^{2}{\left(x \right)} - 2\right) \left(2 \tan^{2}{\left(x \right)} + 2\right)}{2 \tan^{2}{\left(x \right)}} - \left(\pi - 2 x\right) \left(- 2 \tan^{2}{\left(x \right)} - 2\right) + \frac{3 \left(\pi - 2 x\right) \left(- \tan^{2}{\left(x \right)} - 1\right) \left(2 \tan^{2}{\left(x \right)} + 2\right)}{2 \tan^{2}{\left(x \right)}} + \frac{2 \left(- 2 \tan^{2}{\left(x \right)} - 2\right) \left(- \tan^{2}{\left(x \right)} - 1\right)}{\tan^{3}{\left(x \right)}} - \frac{2 \left(2 \tan^{2}{\left(x \right)} + 2\right)}{\tan{\left(x \right)}}}\right)$$
=
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{- \frac{\log{\left(- x + \frac{\pi}{2} \right)}^{3}}{2} - \frac{3 \log{\left(- x + \frac{\pi}{2} \right)}^{2}}{2}}{- 2 x - \frac{8 x}{\tan^{2}{\left(x \right)}} - \frac{6 x}{\tan^{4}{\left(x \right)}} + \pi + \frac{4}{\tan{\left(x \right)}} + \frac{4 \pi}{\tan^{2}{\left(x \right)}} + \frac{4}{\tan^{3}{\left(x \right)}} + \frac{3 \pi}{\tan^{4}{\left(x \right)}}}\right)$$
=
$$\lim_{x \to \frac{\pi}{2}^+}\left(\frac{- \frac{\log{\left(- x + \frac{\pi}{2} \right)}^{3}}{2} - \frac{3 \log{\left(- x + \frac{\pi}{2} \right)}^{2}}{2}}{- 2 x - \frac{8 x}{\tan^{2}{\left(x \right)}} - \frac{6 x}{\tan^{4}{\left(x \right)}} + \pi + \frac{4}{\tan{\left(x \right)}} + \frac{4 \pi}{\tan^{2}{\left(x \right)}} + \frac{4}{\tan^{3}{\left(x \right)}} + \frac{3 \pi}{\tan^{4}{\left(x \right)}}}\right)$$
=
$$0$$
Como puedes ver, hemos aplicado el método de l'Hopital (utilizando la derivada del numerador y denominador) 3 vez (veces)