C++ Program - Find Roots of a Quadratic Equation
A standard form of a quadratic equation is:
ax2 + bx + c = 0
Where:
a, b and c are real numbers and a ≠ 0.
Roots of the equation are:
For Example:
The roots of equation x2 + 5x + 4 = 0 is
The roots of the equation will be imaginary if D = b2 - 4ac < 0. For example - the roots of equation x2 + 4x + 5 = 0 will be
Method : Calculate roots of a Quadratic equation
In the example below, a function called roots is created which takes a, b and c as arguments to calculate the roots of the equation ax2 + bx + c = 0.
#include <iostream> #include <cmath> using namespace std; static void roots(double, double, double); static void roots(double a, double b, double c) { double D = b*b - 4*a*c; if (D >= 0) { double x1 = (-b + sqrt(D))/(2*a); double x2 = (-b - sqrt(D))/(2*a); cout<<"Roots are: "<<x1<<", "<<x2<<"\n"; } else { double x1 = -b/(2*a); double x2 = sqrt(-D)/(2*a); cout<<"Roots are: "<<x1<<"±"<<x2<<"i\n"; } } int main() { cout<<"Equation is x*x+5x+4=0\n"; roots(1,5,4); cout<<"\nEquation is x*x+4x+5=0\n"; roots(1,4,5); return 0; }
The above code will give the following output:
Equation is x*x+5x+4=0 Roots are: -1, -4 Equation is x*x+4x+5=0 Roots are: -2±1i
Recommended Pages
- C++ Program - To Check Prime Number
- C++ Program - Bubble Sort
- C++ Program - Selection Sort
- C++ Program - Maximum Subarray Sum
- C++ Program - Reverse digits of a given Integer
- C++ - Swap two numbers
- C++ Program - Fibonacci Sequence
- C++ Program - Insertion Sort
- C++ Program - Find Factorial of a Number
- C++ Program - Find HCF of Two Numbers
- C++ Program - Merge Sort
- C++ Program - Shell Sort
- Stack in C++
- Queue in C++
- C++ Program - Find LCM of Two Numbers
- C++ Program - To Check Whether a Number is Palindrome or Not
- C++ Program - To Check Whether a String is Palindrome or Not
- C++ Program - Heap Sort
- C++ Program - Quick Sort
- C++ - Swap Two Numbers without using Temporary Variable