Question 1102479
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Let me translate the answer by @Stanbon to the regular Math language:


<pre>
    The solution to the equation arccos(x) = 2 is the real number x = cos(2),  where "2" means the angle of 2 radians.


    Using the tables, a computer or a calculator,  x = cos(2) = -0.41615. . . 
</pre>