In this Java tutorial, you will learn how to find the roots of quadratic equation with a sample code snippet.
How to find the roots of quadratic equation?
RUN CODE SNIPPETJava
x
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public class Main { 2
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public static void main(String[] args) { 4
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double a = 2, b = -5, c = 6; 6
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double root1, root2; 8
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double determinant = b * b - 4 * a * c; 10
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if (determinant > 0) { 12
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root1 = (-b + Math.sqrt(determinant)) / (2 * a); 14
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root2 = (-b - Math.sqrt(determinant)) / (2 * a); 16
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System.out.format("root1 = %.2f and root2 = %.2f", root1, root2); 18
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} 20
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else if (determinant == 0) { 22
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root1 = root2 = -b / (2 * a); 24
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System.out.format("root1 = root2 = %.2f;", root1); 26
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} 28
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else { 30
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double real = -b / (2 * a); 32
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double imaginary = Math.sqrt(-determinant) / (2 * a); 34
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System.out.format("root1 = %.2f+%.2fi", real, imaginary); 36
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System.out.format("\nroot2 = %.2f-%.2fi", real, imaginary); 38
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} 40
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} 42
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}OUTPUT
root1 = 1.25+1.20i root2 = 1.25-1.20i
In the above program the, coefficients of a, b, c are set to 2, -5, 6.
The determinant is calculated using b^2-4ac.
The roots are calculated based on the determinant and to calculate the square root of a number we use the library function Math.sqrt().
