Question 215364
This value is undefined.



Let *[Tex \LARGE x=\sec^{-1}(0)]. 



Now take the secant of both sides to get *[Tex \LARGE \sec(x)=0]



Now use the identity *[Tex \LARGE \sec(x)=\frac{1}{\cos(x)}] to rewrite the equation above to get *[Tex \LARGE \frac{1}{\cos(x)}=0]



So the question is: what are the solutions to *[Tex \LARGE \frac{1}{\cos(x)}=0] ? The answer is there are none. This implies that *[Tex \LARGE \sec^{-1}(0)] is undefined.