secant inverse in terms of cosine inverse?

• Aug 30th 2010, 08:51 PM
curio03
secant inverse in terms of cosine inverse?
What does sec^-1(x) (secant inverse) equal in terms of cos^-1(x) (cosine inverse)?

I know that sec^-1(x) is not equal to 1/(cos^-1(x)).
• Aug 30th 2010, 09:08 PM
Educated
$sec^{-1}(x) = cos^{-1}(\frac{1}{x})$