Question:
$\cos ^{-1}(\cos (-5))+\sin ^{-1}(\sin (6))-\tan ^{-1}(\tan (12))$ is equal to :
(The inverse trigonometric functions take the principal values)
Correct Option: , 3
Solution:
$\cos ^{-1}(\cos (-5))+\sin ^{-1}(\sin (6))-\tan ^{-1}(\tan (12))$
$\Rightarrow(2 \pi-5)+(6-2 \pi)-(12-4 \pi)$
$\Rightarrow 4 \pi-11$