uses crt;
var n,i: integer;
x,s: real;
function pow(x:real;n:integer):real;
var r:real;
i:integer;
begin
r:=x;
for i:=1 to n-1 do
r:=r*x;
pow:=r;
end;
begin
clrscr;
write('n: ');
readln(n);
write('x: ');
readln(x);
for i:=1 to n do
s:=s+pow(sin(x),i);
writeln('Answer: ',s:5:4);
readln;
end.