# Calculate the Discriminant Value

In algebra, Discriminant helps us in deducing various properties of the roots of a polynomial or polynomial function without even computing them. Let’s look at this general quadratic polynomial of degree two:

`ax2 + bx + c`

Here the discriminant of the equation is calculated using the formula:

```b2 – 4ac
```

Now we can deduce the following properties:

• If the discriminant is equal to zero then the polynomial has equal roots i.e., a=b.
• If the discriminant is positive and the coefficients are real, then the polynomial has two real roots.

Here are few conditions that we must keep in mind while programming and making deductions from the discriminant:

• If the discriminant is equal to zero then one solution is possible.
• If the discriminant is positive then two solutions are possible.
• If the discriminant is negative then no real solutions are possible.

Examples:

```Input:
a = 20
b = 30
c = 10
Explanation:
(30**2) - (4*20*10)
Output:
Discriminant is 100 which is positive
Hence Two solutions

Input:
a = 9
b = 7
c = 12
Explanation:
(30**2) - (4*20*10)
Output:
Discriminant is -383 which is negative
Hence no real solutions
```

## C++

 `// CPP program to calculate Discriminant ` `#include ` ` `  `using` `namespace` `std; ` ` `  `void` `discriminant(``int` `a, ``int` `b, ``int` `c){ ` ` `  `    ``int` `discriminant = (b*b) - (4*a*c); ` `    ``if``(discriminant > 0){ ` `        ``cout<<``"Discriminant is "``<

## Java

 `// Java program to calculate discriminant ` `public` `class` `Discriminant{ ` `     `  `    ``// function to calculate discriminant ` `    ``static` `int` `disc(``int` `a, ``int` `b, ``int` `c){ ` `        ``int` `dis = (``int``)Math.pow(b,``2``) - (``4``*a*c); ` `        ``return` `dis; ` `    ``} ` ` `  `    ``// Driver Code ` `    ``public` `static` `void` `main(String args[]){ ` `        ``int` `a=``20``; ` `        ``int` `b=``30``; ` `        ``int` `c=``10``; ` `        ``int` `discriminant = disc(a, b, c); ` `        ``if` `(discriminant > ``0``){ ` `            ``System.out.println(``"Discriminant is "` `+ discriminant  ` `                    ``+ ``" which is Positive"``); ` `            ``System.out.println(``"Hence Two Solutions"``); ` `        ``} ` `        ``else` `if` `(discriminant == ``0``){ ` `            ``System.out.println(``"Discriminant is "` `+ discriminant ` `                    ``+ ``" which is Zero"``); ` `            ``System.out.println(``"Hence One Solution"``); ` `        ``} ` `        ``else` `{ ` `            ``System.out.println(``"Discriminant is "``+ discriminant  ` `                    ``+ ``" which is Negative"``); ` `            ``System.out.println(``"Hence No Real Solutions"``); ` `        ``} ` `    ``} ` `} `

## Python3

 `# Python program to calculate Discriminant ` ` `  `def` `discriminant(a, b, c): ` ` `  `    ``discriminant ``=` `(b``*``*``2``) ``-` `(``4``*``a``*``c) ` `    ``if` `discriminant > ``0``: ` `         `  `        ``print``(``'Discriminant is'``, discriminant, ` `                ``"which is Positive"``) ` `                 `  `        ``print``(``'Hence Two Solutions'``) ` `         `  `    ``elif` `discriminant ``=``=` `0``: ` `         `  `        ``print``(``'Discriminant is'``, discriminant,  ` `                ``"which is Zero"``) ` `                 `  `        ``print``(``'Hence One Solution'``) ` `         `  `    ``elif` `discriminant < ``0``: ` `         `  `        ``print``(``'Discriminant is'``, discriminant,  ` `                ``"which is Negative"``) ` `                 `  `        ``print``(``'Hence No Real Solutions'``) ` ` `  `# Driver Code ` `a ``=` `20` `b ``=` `30` `c ``=` `10` `discriminant(a, b, c) `

## C#

 `// C# program to calculate ` `// discriminant ` `using` `System; ` ` `  `class` `GFG ` `{ ` ` `  `// function to calculate ` `// discriminant ` `static` `int` `disc(``int` `a,  ` `                ``int` `b, ``int` `c) ` `{ ` `    ``int` `dis = (``int``)Math.Pow(b, 2) -  ` `                    ``(4 * a * c); ` `    ``return` `dis; ` `} ` `     `  `// Driver Code ` `public` `static` `void` `Main() ` `{ ` `    ``int` `a = 20; ` `    ``int` `b = 30; ` `    ``int` `c = 10; ` `    ``int` `discriminant = disc(a, b, c); ` `    ``if` `(discriminant > 0) ` `    ``{ ` `        ``Console.WriteLine(``"Discriminant is "` `+  ` `                                ``discriminant +  ` `                        ``" which is Positive"``); ` `        ``Console.WriteLine(``"Hence Two Solutions"``); ` `    ``} ` `     `  `    ``else` `if` `(discriminant == 0) ` `    ``{ ` `        ``Console.WriteLine(``"Discriminant is "` `+  ` `                                ``discriminant +  ` `                            ``" which is Zero"``); ` `        ``Console.WriteLine(``"Hence One Solution"``); ` `    ``} ` `     `  `    ``else` `    ``{ ` `        ``Console.WriteLine(``"Discriminant is "``+  ` `                            ``discriminant +  ` `                    ``" which is Negative"``); ` `        ``Console.WriteLine(``"Hence No Real Solutions"``); ` `    ``} ` `} ` `} ` ` `  `// This code is contributed ` `// by anuj_67. `

## PHP

 ` 0) ` `    ``{ ` `        ``echo` `"Discriminant is "``, ``\$discriminant``,  ` `             ``" which is Positive\n"``; ` `        ``echo` `"Henco Two Solutions"``; ` `    ``} ` `     `  `    ``else` `if``(``\$discriminant` `== 0) ` `    ``{  ` `        ``echo` `"Discriminant is "``, ``\$discriminant``,  ` `             ``" which is Zero\n"``;  ` `        ``echo` `"Hence One Solution"``;  ` `    ``}  ` `     `  `    ``else` `if``(``\$discriminant` `< 0) ` `    ``{  ` `        ``echo` `"Discriminant is "``, ``\$discriminant``,  ` `             ``" which is Negative\n"``;  ` `             `  `        ``echo` `"Hence No Real Solutions"``;  ` `    ``}  ` `} ` ` `  `// Driver code ` `\$a` `= 20; ` `\$b` `= 30; ` `\$c` `= 10; ` ` `  `// function call to print discriminant ` `discriminant(``\$a``, ``\$b``, ``\$c``); ` ` `  `// This code is contributed  ` `// by Shashank_Sharma ` `?> `

Output:

```Discriminant is 100 which is Positive
Hence Two Solutions
```

This article is contributed by Chinmoy Lenka. If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

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