Problem Statement

Implement the algorithm to compute the principal   nth   root

A

n

{\displaystyle {\sqrt[{n}]{A}}}

of a positive real number   A,   as explained at the   Wikipedia page.

Let's start with the solution:

sub infix:<√>($n, $A) {
    .tail given $A / $n, { (($n-1) * $_+ $A / ($_** ($n-1))) / $n } ... * ≅ *;
}

use Test;
plan 9;
is-approx ($_√pi)**$_, pi for 2 .. 10;