Newton's method of calculating a square root.
★★☆5² = 25, so √25 = 5, or expressed another way, 5 * 5 = 25, so the square root of 25 is 5. Newton's method is one way to calculate the square root of a number.
Write a program that outputs the square root of a number using Newton’s method.
Remember to add a comment before a subprogram, selection or iteration statement to explain its purpose.
sqroot that:For example, the square root of 64 can be calculated in the sequence of steps:
64
32.5
17.234615384615385
10.474036101145005
8.292191785986859
8.005147977880979
8.000001655289593
8.00000000000017
8.0
8.0 – This value equals the previous value of root, so the algorithm is complete.
Enter a number:
25
The square root of 25.0 is 5.0
Enter a number:
64
The square root of 64.0 is 8.0
// Square root program
using System;
class Submission
{
---
// -------------------------
// Subprograms
// -------------------------
// Function to calculate the square root of a number using Newton's method
---
static double sqroot(double x)
{
---
double root = x;
double last_root = 0;
while (root != last_root)
{
---
last_root = root;
root = 0.5 * (root + (x / root));
---
}
---
return root;
---
}
---
// -------------------------
// Main program
// -------------------------
public static void Main(string[] args)
{
---
Console.WriteLine("Enter a number:");
double num = Convert.ToDouble(Console.ReadLine());
---
Console.WriteLine($"The square root of {num} is {sqroot(num)}");
---
}
---
}