Complex cube roots

exercise5.go

package main

import (
    "fmt"
    "math/cmplx"
    )

func Cbrt(x complex128) complex128 {
    var z complex128 = 1 
    for i := 0 ; i < 50 ; i++ {
    	z = z - (z * z * z - x) / (3 * z * z) 
    }
    return z
}

func main() {
    fmt.Println(Cbrt(2))
    fmt.Println(cmplx.Pow(Cbrt(2), 3))
}