Function Sqrt (X : Real) : Real;
Sqrt returns the square root of its argument X, which must be positive.
If X is negative, then a run-time error is generated.
Program Example66;
{ Program to demonstrate the Sqrt function. }
begin
Writeln (Sqrt(4):0:3); { Prints 2.000 }
Writeln (Sqrt(2):0:3); { Prints 1.414 }
end.