https://go.dev/tour/flowcontrol/8

sqrt.go

package main

import (
	"fmt"
	"math"
)

func Sqrt(x float64) float64 {
	guess := 1.0
	previousGuess := 1.0
	maxVariance := 1e-8

	fmt.Println("Finding square root of ", x)

	for i := 1; i <= 10; i++ {
		previousGuess = guess
		guess -= (guess*guess - x) / (2 * guess)

		fmt.Println("iteration ", i, " result:", guess)

		if math.Abs(guess-previousGuess) < maxVariance {
			fmt.Println("Square root found at iteration ", i)

			return guess
		}

	}

	return guess
}

func main() {
	for i := 1; i <= 10; i++ {
		fmt.Println("Square root of ", i, ": ", Sqrt(float64(i)))
	}
}