The arccosine value of  0  is 1.5708 
*** TEST #1 PASSED ***
The arccosine value of  .5  is 1.0472 
*** TEST #2 PASSED ***
The arccosine value of -.5  is 2.0944 
*** TEST #3 PASSED ***
The arccosine value of  1  is 0 
*** TEST #4 PASSED ***
The arccosine value of -1  is 3.14159 
*** TEST #5 PASSED ***
*** ALL TESTS PASSED ***
