Using your calculator, find a solution for http://webwork.mathstat.concordia.ca...631e7925d1.png in RADIANS (if possible). If no solution exists, enterNONE.

Though many solutions may exist, you should only provide ONE answer (which comes from using the inverse trigonometric function keys on your calculator).

http://webwork.mathstat.concordia.ca...706f2789c1.png when http://webwork.mathstat.concordia.ca...c0a1902111.png (round your answer to four decimal places)

I got what I believe to be the answer but I am being told its wrong

so i take

Are my calculation correct?