\cot \left(\tan ^{-1} x+\cot ^{-1} x\right)= ?
(A) 0
(B) 1
(C) \frac{1}{2}
(D) \frac{\pi}{4}
\cot \left(\tan ^{-1} x+\cot ^{-1} x\right)= ?
(A) 0
(B) 1
(C) \frac{1}{2}
(D) \frac{\pi}{4}

Correct option is (A) 0
Sol:- The given relation should be

    \[\begin{array}{l} \cot \left(\tan ^{-1} x+\cot ^{-1} x\right) \\ \text { we know } \tan ^{-1} x+\cot ^{-1} x=\frac{\pi}{2} \\ \therefore \cot \left(\frac{\pi}{2}\right)=0 \text { Ans } \end{array}\]