$\frac{\mathit{Co}s\mathit{13}\mathit{-}\mathit{Sin}\mathit{13}}{\mathit{Cos}\mathit{13}\mathit{+}\mathit{Sin}\mathit{13}}\mathit{+}\frac{\mathit{1}}{\mathit{Cot}\mathit{148}}\mathit{=}$

$\frac{(\cos 13-\sin 13{)}^2}{{\cos }^{2}13-{\sin }^{2}13}+\tan 148°$

$\frac{1-\sin 26}{\cos 26}+\tan (180-32)$

$\frac{1-\cos 64}{\sin 64}-\tan 32$

$we know that \frac{1-\cos \theta }{\sin \theta }=\tan \frac{\theta }{2}$

$\tan 32 - \tan 32 =0$