Answer:
#include <iostream>
#include <cmath>
using namespace std;
//initialize function quadratic
void quadratic(double, double, double);
int main() {
//declare double variables a, b and c
double a,b,c;
//take input from user
cin>>a>>b>>c;
//call function quadratic
quadratic(a,b,c);
return 0;
}
void quadratic(double a, double b, double c){
double root,n;
//check if variable a is equal to zero
if(a==0){
cout<<"no solution for a=0"<<endl;
return;
}
//check if b squared - 4ac is less than zero
else
if(((b*b)-(4*a*c))<0){
cout<<"no real solutions"<<endl;
return;
}
//print the largest root if the above conditions are not satisfied
else{
n=((b*b)-(4*a*c));
root=(-b + sqrt(n)) / (2*a);
cout<<"Largest root is:"<<root<<endl;
}
return ;
}
Explanation:
Read three double variables a, b and c from the user and pass it to the function quadratic. Check if the value of variable a is equal to zero. If true, print "no solution for a=0". If this condition is false, check if b squared - 4ac is less than zero. If true, print "no real solutions". If this condition is also false, calculate the largest solution using the following formula:
largest root = (-b + square root of (b squared - 4ac)) / (2*a)
Input 1:
2 5 3
Output 2:
Largest root is:-1
Input 2:
5 6 1
Output 2:
Largest root is:-0.2
