1.
uses crt;
var a,b: integer;
begin
clrscr;
    readln(a,b);
    if (a=0) and (b=0) then writeln('BPT vo so nghiem') else
    if (a=0) and (b<>0) then writeln('BPT vo nghiem') else writeln('Tap nghiem cua pt la: S={x|x>',-b/a,'}');
    readln
end.
2.
uses crt;
var n,i,s,s2: integer;
begin
clrscr;
    readln(n);
    for i:=1 to n do begin
        s:=s+i;
        if i mod 2=0 then s:=s+i;
    end;
    writeln('Tong n so tu nhien dau tien: ',s);
    writeln('Tong n so tu nhien chan dau tien: ',s2);
    readln
end.

Bài 1:

uses crt;
var a,b: integer;
x: real;
begin
write ('nhap a: ');  readln(a);

write ('nhap b: ');  readln (b);
if (a=0) and (b=0) then writeln ('BPT co vo so nghiem')
else if (a=0) and (b<>0) then writeln ('BPT vo nghiem')

else

writeln('Nghiem cua BPT la: x> ',-b/a);

readln;
end.

---------------------------
Bài 2:

uses crt;

var a: array[1..100] of integer;

i,n,s,ss: integer;

begin

clrscr;

write ('nhap N: ');  readln (n);

s:=0;

ss:=0;

for i:=1 to n do

begin

write ('nhap so thu ',i,': ');  readln (a[i]);

s:=s+a[i];

if (a[i]<=n) and (a[i] mod 2=0) then ss:=ss+i;

end;

writeln ('Tong cac so la: ',s);

writeln ('Tong cac so chan nho hon hoac bang ',n,': ',ss);

readln;

end.