package main

import (
	"fmt"
	"math"
)

func Sqrt(x float64) float64 {
	z := 1.0
	for (z*z - x) > 0.0001 || (z*z - x) < 0 {
		z -= (z*z - x) / (2*z)
		fmt.Println(z)
	}
	return z
}

func main() {
	fmt.Println(Sqrt(9))
	fmt.Println(math.Sqrt(9))
}