Thanks @DanielPiker, that helped a lot.
In the end I used this code:
and found the component name from here:
var com = rd.Components.FindComponent("Meshedit2000_3DConvexHull");
object[] args = new object[] {x};
string[] warnings;
if (com != null)
{
var results = com.Evaluate(args, false, out warnings);
A = results[0];
}