question_answer

\[\sin \left\{ {{\tan }^{-1}}\left( \frac{1-{{x}^{2}}}{2x} \right)+{{\cos }^{-1}}\left( \frac{1-{{x}^{2}}}{1+{{x}^{2}}} \right) \right\}\]  is equal to

A)  \[0\]                            

B)  \[1\]

C)  \[\sqrt{2}\]                               

D)  \[\frac{1}{\sqrt{2}}\]

E)  None of these