1.

program ctpt;

uses crt;

  var t, v, a, tb: real;

            e: integer;

begin

           clrscr;

           write('Nhap diem trung binh mon toan: '); readln(t);

           write('Nhap diem trung binh mon van: '); readln(v);

           write('Nhap diem trung binh mon anh: '); readln(a);

           tb:=(t*2+v*2+a)/5;

           write('Diem trung binh cac mon: ', tb:4:1);

           if (tb>=8) and (t>=8) and (v>=8) and (a>=8) then write('Gioi') else

             if (tb>=6.5) and (t>=6.5) and (v>=6.5) and (a>=6.5) then write('Kha') else

                if (tb>=5) and (t>=5) and (v>=5) and (a>=5) then write('TB') else

                  if (tb>=3.5) and (t>=3.5) and (v>=3.5) and (a>=3.5) then write('Yeu') else

                             write('Kem');

            if (t<v) and (v<a) then begin write('Tang dan: ',t:3, v:3, a); write('Giam dan: ', a:3, v:3, t); end;

            if (v<t) and (t<a) then begin write('Tang dan: ',v:3, t:3, a); write('Giam dan: ', a:3, t:3, v); end;

            if (t<a) and (a<v) then begin write('Tang dan: ',t:3, a:3, v); write('Giam dan: ', v:3, a:3, t); end;

            if (v<a) and (a<t) then begin write('Tang dan: ',v:3, a:3, t); write('Giam dan: ', t:3, a:3, v); end;

            if (a<t) and (t<v) then begin write('Tang dan: ', a:3, t:3, v); write('Giam dan: ', v:3, t:3, a); end;

            if (a<v) and (v<t) then begin write('Tang dan: ', a:3, v:3, t); write('Giam dan: ', t:3, v:3, a); end;

            readln

end.

2.

proram ctpt;

var a, b, c, dt: integer;

begin

            clrscr;

            write('Nhap a = '); readln(a);

            write('Nhap b = '); readln(b);

            write('Nhap c = '); readln(c);

            d:=0;

            if (a = 0) and (b = 0) and (c = 0) then writeln('Phuong trinh co vo so nghiem');

            if (a = 0) and (b = 0) and (c <> 0) then writeln('Phuong trinh vo nghiem');

            if (a = 0) and (b <> 0) then writeln('Nghiem cua phuong trinh la: '-c/b:4:1);

            if (a <> 0) then

            begin

                  dt:=b*b-4*a*c;

                  if d<0 then writeln('Phuong trinh vo nghiem');

                  if d=0 then writeln('Phuong trinh co 2 nghiem kep: x1 = x2 = ',-b/(2*a):4:1);

                  if d>0 then writeln('Phuong trinh co 2 nghiem: x1 = ',(-b-sqrt(a))/(2*a):4:1,'; x2 = ',(-b-sqrt(d))/(2*a):4:1);

             end;

             readln

end.

uses crt;
var tb,v,t,ta,p:real;
begin
clrscr;
   write('Nhap diem van, toan, tieng anh: ');readln(v,t,ta);
   tb:=(v*2+t*2+ta)/5;
   if tb>8.5 then writeln('Gioi') else
   if tb>6.5 then writeln('Kha') else
   if tb>5 then writeln('Trung binh') else
   if tb>3.5 then writeln('Yeu');
   if t<v then begin p:=t; t:=v; v:=p; end;
   if v<ta then begin p:=ta; ta:=v; v:=p; end;
   if t<ta then begin p:=t; t:=ta; ta:=p; end;
   writeln('Tang dan: ',t:0:2,' ',v:0:2,' ',ta:0:2);
   writeln('Tang dan: ',ta:0:2,' ',v:0:2,' ',t:0:2);
readln;
end.