to about :a :b
  output and [:a - :b < 1e-5] [:a - :b > -1e-5]
end

to root :n :a [:guess :a]
  localmake "next ((:n-1) * :guess + :a / power :guess (:n-1)) / n
  if about :guess :next [output :next]
  output (root :n :a :next)
end

show root 5 34   ; 2.02439745849989