Considerando $0 $$\det \left(\begin{array}{cc} {\log\ \left(\hspace{2pt}\mathrm{tg}\ \left(x\right)\right)} & {\log\ \left(\hspace{2pt}\mathrm{cotg}\ \left(x\right)\right)} \\ {1} & {1} \end{array}\right)=0$$ é
Considerando $0 $$\det \left(\begin{array}{cc} {\log\ \left(\hspace{2pt}\mathrm{tg}\ \left(x\right)\right)} & {\log\ \left(\hspace{2pt}\mathrm{cotg}\ \left(x\right)\right)} \\ {1} & {1} \end{array}\right)=0$$ é