I'm dealing with a analysis of a mechanical mode with maple12,but I got blocked with ploting a function for a long time.Could you help me with it?Thanks a million!

the expression is below:

arcsin((2.*(22.*RootOf(-73-55*sin(theta[1])+2*_Z^2, label = _L3)+10.*RootOf(-73-55*sin(theta[1])+2*_Z^2, label = _L3)*sin(theta[1])-73.-55.*sin(theta[1])))/(73.+55.*sin(theta[1])));

when ploting that,it appears:Warning, unable to evaluate the function to numeric values in the region; see the plotting command's help page to ensure the calling sequence is correct.