Câu 1

uses crt;
var a,b,c: real;
begin
clrscr;
     write('Nhap a = '); readln(a);
     write('Nhap b = '); readln(b);
     write('Nhap c = '); readln(c);
     if (a+b+c=180) then
     begin
      writeln('La so do ba canh cua mot tam giac');
        if (a = b) and (b = c) then writeln('La tam giac deu')
        else if (a = b) or (b = c) or (a = c) then if (a*a = b*b+c*c) or (b*b = c*c+a*a) or  (c*c= a*a+b*b)then writeln('La tam giac vuong can') else writeln('La tam giac can')  else
if (a*a = b*b+c*c) or (b*b = c*c+a*a) or (c*c= a*a+b*b) then writeln('La tam giac vuong') else writeln('La tam giac thuong');
end
else writeln('Khong phai la so do ba canh cua mot tam giac');
readln
End.

Câu 2:

uses crt;

var s,i:integer;

begin

s:=0;

for i:=1 to 50 do

s:=s+i;

write('Tong: ',s);

readln

end.

1) uses crt;
var a,b,c:real;
kt:integer;
begin
clrscr;
write('Nhap a='); readln(a);
write('Nhap b='); readln(b);
write('Nhap c='); readln(c);
if (a+b>c) and (a+c>b) and (b+c>a) and (a>0) and (b>0) and (c>0) then
begin
kt:=0;
if sqr(a)=sqr(b)+sqr(c) then kt:=1;
if sqr(b)=sqr(a)+sqr(c) then kt:=1;
if sqr(c)=sqr(a)+sqr(b) then kt:=1;
if (a=b) and (a<>c) and (b<>c) then kt:=2;
if (b=c) and (b<>a) and (c<>a) then kt:=2;
if (c=a) and (c<>b) and (a<>b) then kt:=2;
if (a=b) and (b=c) then kt:=3;
if kt=0 then writeln('Day la tam giac thuong');
if kt=1 then writeln('Day la tam giac vuong');
if kt=2 then writeln('Day la tam giac can');
if kt=3 then writeln('Day la tam giac deu');
if (kt=1) and (kt=2) then writeln('Day la tam giac vuong can');
end
else writeln('Day khong la ba canh cua mot tam giac');
readln;
end.

program Tinh_tong;

2)uses crt;

var S,i:integer;

begin

S:=0;

for i:=1 to 50 do S:=S+i;

writeln('Tong tu 1 den 50 la:',S);

readln

end.