Tham khảo:

import math

def giai_phuong_trinh_bac_2(a, b, c):

delta = b**2 - 4*a*c

 if delta < 0:

  return None

 elif delta == 0:

  nghiem = -b / (2*a)

  return (nghiem)

 else:

  sqrt_delta = math.sqrt(delta)

  nghiem1 = (-b + sqrt_delta) / (2*a)

  nghiem2 = (-b - sqrt_delta) / (2*a)

  return (nghiem1, nghiem2)

const fi='dulieu.inp';

fo='kq.inp';

var f1,f2:text;

a,b,c,delta:real;

begin

assign(f1,fi); reset(f1);

assign(f2,fo); rewrite(f2);

readln(f1,a,b,c);

delta:=sqr(b)-4*a*c;

if delta<0 then writeln(f2,'Phuong trinh vo nghiem');

if delta=0 then writeln(f2,'Phuong trinh co nghiem kep la: ',-b/(2*a):4:2);

if delta>0 then 

begin

writeln(f2,'Nghiem thu nhat la: ',(-b+sqrt(delta))/(2*a):4:2);

writeln(f2,'Nghiem thu hai la: ',(-b-sqrt(delta))/(2*a):4:2);

end;

close(f1);

close(f2);

end. 

Cảm ơn nha

uses crt; 
var a, b: logint; 
Begin 
write('nhap so a ='); Readln(a); 
write('nhap so b ='); readln(b); 
If (a = 0 and b = 0) 
then write ('pt co nghiem x thuoc R') 
else 

tuy mk ngu pascal nhưng mk vẫn bt là bn lm sai r :)

mình đang cần gấp ạ

Help me

#include <bits/stdc++.h>
using namespace std;
double a,b,c,delta,x1,x2;
int main()
{
    //freopen("PTB2.inp","r",stdin);
    //freopen("PTB2.out","w",stdout);
    cin>>a>>b>>c;
    delta=(b*b-4*a*c);
    if (delta<0) cout<<"-1";
    if (delta==0) cout<<fixed<<setprecision(5)<<(-b/(2*a));
    if (delta>0)
    {
        x1=(-b-sqrt(delta))/(2*a);
        x2=(-b+sqrt(delta))/(2*a);
        cout<<fixed<<setprecision(5)<<x1<<" "<<fixed<<setprecision(5)<<x2;
    }
    return 0;
}

uses crt;

const fi='input.txt';

fo='output.txt';

var f1,f2:text;

a,b:integer;

begin

assign(f1,fi); reset(f1);

assign(f2,fo); rewrite(f2);

readln(f1,a,b);

if (a=0) and (b=0) then writeln(f2,'Phuong trinh co vo so nghiem');

if (a<>0) then writeln(f2,-b/a:4:2);

if (a=0) and (b<>0) then writeln(f2,'Phuong trinh vo nghiem');

close(f1);

close(f2);

end.