I need help solving for y' using implicit differentiation for the following problems.. I don't know how to do it when it involves "e" or sin, cos, etc., as well as the last problem.. I know its a lot of work but I am really stuck here..

e^(x/y) = x - y

sqrt(xy) = 1 + x^(2)y

e^(y)cos(x) = 1 + sin(xy)