public TwoDimensionalFunction()
 {
     NumArgs = 2;
     f1 = new Poly();
     f2 = new Poly();
     Title = "2-мерн.";
 }
 public ThreeDimensionalFunction()
 {
     NumArgs = 3;
     f1 = new Poly();
     f2 = new Poly();
     f3 = new Trig();
     Title = "3-мерн.";
 }