# Math Help - secant inverse in terms of cosine inverse?

1. ## 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)).

2. $sec^{-1}(x) = cos^{-1}(\frac{1}{x})$