Java Code:
class TrigFun
{
public static void main(String[] args)
{
     double rads, degs, tanA, aTanA, coTanA;

     // Obtain angle in degrees from user
     degs = 120d;
     // Convert degrees to radian
     rads = Math.toRadians(degs);

     // Calculate tangent
     tanA = Math.tan(rads);
     System.out.println("Tangent = " + tanA);

     // Calculate cotangent
     coTanA = 1.0/Math.tan(rads);
     System.out.println("Cotangent = " + coTanA);

     // Calculate arc-tangent
     rads = Math.atan(tanA);
     degs = Math.toDegrees(rads);
     System.out.println("Arc tangent: "  + degs);

     // Calculate arc-cotangent
     rads = Math.atan(1/coTanA);
     degs = Math.toDegrees(rads);
     System.out.println("Arc cotangent: "  + degs); 
}
}