Câu 1:
program CauHoi;
uses crt;
var i,n :integer; S :qword;
begin
write('Nhap so n: '); readln(n);
For i:=1 to n do S:=S+2*i;
writeln('Ket qua la: ',S);
readln;
end.
Thêm câu 2 này
program CauHoi;
uses crt;
var i,n :integer; S :qword;
begin
write('Nhap so n: '); readln(n);
For i:=1 to n do S:=S+(2*i)+1;
writeln('Ket qua la: ',S);
readln;
end.