ACOS _ _ _ _ _ _ _ _ _ _ _ _ operator

The acos operator returns the arccosine of its argument.

syntax:

<expression> may be any scalar REDUCE expression, not an array, matrix or vector expression. <simple\_expression> must be a single identifier or begin with a prefix operator name.

examples:

acos(ab); 

  ACOS(AB) 


acos 15; 

  ACOS(15) 


df(acos(x*y),x); 

           2  2
  SQRT( - X *Y  + 1)*Y
  -------------------- 
        2  2
       X *Y  - 1


on rounded; 

res := acos(sqrt(2)/2); 

  RES := 0.785398163397 


res-pi/4; 

  0

An explicit numeric value is not given unless the switch rounded is on and the argument has an absolute numeric value less than or equal to 1.