[Edit] C++: Math functions: sqrt() (#7270)

* [Edit] C++: Math functions: sqrt()

* Update sqrt.md

* Update content/cpp/concepts/math-functions/terms/sqrt/sqrt.md

* Update content/cpp/concepts/math-functions/terms/sqrt/sqrt.md

* Update content/cpp/concepts/math-functions/terms/sqrt/sqrt.md

---------

Author: mamtawardhani

content/cpp/concepts/math-functions/terms/sqrt/sqrt.md

@@ -1,59 +1,139 @@
 ---
 Title: 'sqrt()'
-Description: 'Returns square root of the argument.'
+Description: 'Returns the square root of a number in C++.'
 Subjects:
+  - 'Code Foundations'
   - 'Computer Science'
 Tags:
+  - 'Algorithms'
   - 'Functions'
-  - 'Arithmetic'
+  - 'Math'
 CatalogContent:
   - 'learn-c-plus-plus'
   - 'paths/computer-science'
 ---
 
-The **`sqrt()`** function returns the square root of the argument.
+C++ **`sqrt()`** function returns the square root of a number. This mathematical function is part of the C++ standard library and is defined in the `<cmath>` header file.
 
-## Syntax
+## Syntax of C++ `sqrt()`
 
 ```pseudo
-sqrt(x)
+sqrt(num)
 ```
 
-If the parameter `x` is negative (less than 0), then a domain error will occur.
+**Parameters:**
 
-## Example
+- `num`: A floating-point number (double, float, or long double) for which the square root is to be calculated
 
-The following example uses the `sqrt()` function to find the square root of `4`:
+**Return value:**
+
+The `sqrt()` function returns the square root of the given argument as a floating-point value. Its return type matches the type of the argument (e.g., float, double, or long double).
+
+> **Note:** If a negative argument is passed to `sqrt()`, a domain error occurs and the function returns `NaN` (Not a Number).
+
+## Example 1: Basic Usage of `sqrt()` function
+
+This example demonstrates the basic usage of the `sqrt()` function with different numerical values:
+
+```cpp
+#include <iostream>
+#include <cmath>
+using namespace std;
+
+int main() {
+  // Calculate square root of different numbers
+  cout << "Square root of 16: " << sqrt(16) << endl;
+  cout << "Square root of 25: " << sqrt(25) << endl;
+  cout << "Square root of 2: " << sqrt(2) << endl;
+  cout << "Square root of 100.5: " << sqrt(100.5) << endl;
+
+  return 0;
+}
+```
+
+This example results in the following output:
+
+```shell
+Square root of 16: 4
+Square root of 25: 5
+Square root of 2: 1.41421
+Square root of 100.5: 10.025
+```
+
+> **Note:** Output may vary slightly depending on platform-specific floating-point rounding.
+
+## Example 2: Distance Calculation using C++ `sqrt()`
+
+This example shows how `sqrt()` is used to calculate the distance between two points using the Pythagorean theorem:
 
 ```cpp
 #include <iostream>
 #include <cmath>
+using namespace std;
 
 int main() {
-  double x = 4;
-  double result;
+  // Calculate distance between two points (x1, y1) and (x2, y2)
+  double x1 = 1.0, y1 = 2.0;
+  double x2 = 4.0, y2 = 6.0;
+
+  // Apply distance formula: sqrt((x2-x1)^2 + (y2-y1)^2)
+  double distance = sqrt(pow(x2 - x1, 2) + pow(y2 - y1, 2));
 
-  result = std::sqrt(x);
+  cout << "Distance between points (" << x1 << ", " << y1 << ") and ("
+       << x2 << ", " << y2 << ") is: " << distance << endl;
 
-  std::cout << "The square root of " << x << " is " << result << "\n";
-  // Output: The square root of 4 is 2
+  return 0;
 }
 ```
 
-## Codebyte Example
+This example results in the following output:
 
-The following example is runnable and returns the square root of `9` with the `sqrt()` function:
+```shell
+Distance between points (1, 2) and (4, 6) is: 5
+```
+
+## Codebyte Example: Using `sqrt()` to Solve Quadratic Equation
+
+This example demonstrates using `sqrt()` to solve a quadratic equation using the quadratic formula:
 
 ```codebyte/cpp
 #include <iostream>
 #include <cmath>
+using namespace std;
 
 int main() {
-  double x = 9;
-  double result;
+  // Solve quadratic equation ax^2 + bx + c = 0
+  double a = 1.0, b = -5.0, c = 6.0;
+
+  // Calculate discriminant
+  double discriminant = b * b - 4 * a * c;
 
-  result = std::sqrt(x);
+  if (discriminant >= 0) {
+    // Calculate roots using quadratic formula
+    double root1 = (-b + sqrt(discriminant)) / (2 * a);
+    double root2 = (-b - sqrt(discriminant)) / (2 * a);
 
-  std::cout << "The square root of " << x << " is " << result << "\n";
+    cout << "For equation " << a << "x^2 + " << b << "x + " << c << " = 0" << endl;
+    cout << "Root 1: " << root1 << endl;
+    cout << "Root 2: " << root2 << endl;
+  } else {
+    cout << "No real roots exist for this equation." << endl;
+  }
+
+  return 0;
 }
 ```
+
+## Frequently Asked Questions
+
+### 1. What happens if I pass a negative number to `sqrt()`?
+
+Passing a negative number to `sqrt()` results in a domain error and returns `NaN` (Not a Number).
+
+### 2. What header file do I need to include to use `sqrt()`?
+
+You need to include the `<cmath>` header file to use the `sqrt()` function.
+
+### 3. What is the return type of the function `sqrt()` in C++?
+
+The `sqrt()` function returns a floating-point value of the same type as the input parameter. If you pass a float, it returns a float; if you pass a double, it returns a double, and if you pass a long double, it returns a long double.