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Section: Mathematical Functions
Computes the inverse hyperbolic cosine of its argument. The general syntax for its use is
y = acosh(x)
 where x is an n-dimensional array of numerical type. 
The acosh function is computed from the formula 
![\[ \cosh^{-1}(x) = \log\left(x + (x^2 - 1)^0.5\right) \]](form_41.png) 
 where the log (and square root) is taken in its most general sense. 
Here is a simple plot of the inverse hyperbolic cosine function
--> x = linspace(1,pi);
--> plot(x,acosh(x)); grid('on');
