câu 1:
uses crt;
var x: integer;
begin
clrscr;
write ('nhap x: '); readln (x);
writeln ('can bac hai cua x la: ',sqrt(x):1:2);
readln;
end.
câu 2:
uses crt;
var i,n,s: integer;
begin
clrscr;
write ('nhap n: '); readln (n);
for i:=1 to n do s:=s+i;
writeln ('tong la: ',s);
readln;
end.