Kotlin program to find all the roots of a quadratic equation

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In this program, you will learn to find all the roots of a quadratic equation (depending on the determinant) and print them using format() in Kotlin.

The standard form of a quadratic equation is:

ax2　+　bx　+　c = 0, where a, b, and c are real numbers, a ≠ 0

The b2-4ac is called the determinant of the quadratic equation. The determinant explains the nature of the roots.

• If the determinant is greater than 0, then the roots are real and different.

• If the determinant is equal to 0, then the roots are real and equal.

• If the determinant is less than 0, then the roots are complex and different.

Example: Kotlin program to find the roots of a quadratic equation

fun main(args: Array<String>) {
　　　　val a =　2.3
　　　　val b =　4
　　　　val c =　5.6
　　　　val root1: Double
　　　　val root2: Double
　　　　val output: String
　　　　val determinant = b　*　b　-　4.0　*　a　*　c
　　　　//Condition for real different roots
　　　　if (determinant > 0) {
　　　　　　　　root1　= (-b　+　Math.sqrt(determinant))　/　(2　*　a)
　　　　　　　　root2　= (-b　-　Math.sqrt(determinant))　/　(2　*　a)
　　　　　　　　output = "root1　= %.2f and root2　= %.2f".format(root1, root2)
　　　　}
　　　　//Condition for real equal roots
　　　　else if (determinant == 0.0) {
　　　　　　　　root2　=　-b　/　(2　*　a)
　　　　　　　　root1　= root2
　　　　　　　　output = "root1　= root2　= %.2f;".format(root1)
　　　　}
　　　　//If the root is not a real number
　　　　else {
　　　　　　　　val realPart =　-b　/　(2　*　a)
　　　　　　　　val imaginaryPart = Math.sqrt(-determinant)　/　(2　*　a)
　　　　　　　　output = "root1　= %.2f+%.2fi and root2　= %.2f-%.2fi".format(realPart, imaginaryPart, realPart, imaginaryPart)
　　　　}
　　　　println(output)
}

When running the program, the output is:

root1　=　-0.87+1.30i and root2　=　-0.87-1.30i

In the above program, the coefficients a, b, and c are set to2.3,4and5.6. Then, calculate the determinant as b² - 4ac.

According to the value of the determinant, calculate the root according to the above formula. Note that we have already used the library functionMath.sqrt()To calculate the square root of a number.

Then use the standard library function format() to store the output to be printed in a string variable. Then use println() to output the printed output output .

Here is the equivalent Java code for the above program:Java Program for Finding All Roots of a Quadratic Equation

Comprehensive Collection of Kotlin Examples