From this page, https://en.wikipedia.org/wiki/Inverse_hyperbolic_functions, I see that ##\sinh(\cosh^{-1}(x) = \sqrt{x^2 - 1}##, for |x| > 1.Clara Chung said:Homework Statement
View attachment 214910
Homework Equations
The Attempt at a Solution
The attempt is in the picture. Is this the right method? Is there any faster method without cumbersome calculations?
Thank you. I get the answer.Mark44 said:From this page, https://en.wikipedia.org/wiki/Inverse_hyperbolic_functions, I see that ##\sinh(\cosh^{-1}(x) = \sqrt{x^2 - 1}##, for |x| > 1.
LCKurtz said:@Clara Chung: The problem is, if you look at the graph it looks like there is a solution ##x=-\frac 3 4##. And you can check that works exactly in your last equation of your original post but not your root solution.