Const
 n=30;
 x=20.0;
 Eps=1E-9;
Var
 i:Word;
 Q,a,S:Extended;
Begin
 Q:=1;
 For i:=1 to n do
  Q:=Q*(x/2)/i;
 a:=1;
 S:=a;
 i:=0;
 Repeat
  Inc(i);
  a:=-a*Sqr(x/2)/i/(n+i);
  S:=S+a;
 Until Abs(Q*a)<Eps;
 S:=S*Q;
 Writeln('Result: ',S:0:15);
 Readln
End.

Const
 x=0.12;
 Eps=1E-4;
Var
 i:Word;
 a,S:Real;
Begin
 a:=1;
 S:=a;
 i:=0;
 Repeat
  Inc(i);
  a:=a/Cos(Pi/3*(i-1))*Cos(Pi/3*i)*x/i;
  S:=S+a;
 Until Abs(a)<Eps;
 Writeln('Result: ',S:0:8);
 Readln
End.