From: Sergio Arbeo <serabe@...>
Date: 2009-07-11T20:06:36+09:00
Subject: Re: Math cube root

def cube_root(x)
  Math.exp(Math.log(x.to_f)/3.to_f)
end

Cheers,

Serabe

P.D. Proof:
Cube root of x is equal to x^(1/3)

x^(1/3) = y
ln(x^(1/3)) = ln y
(1/3)ln x = ln y

Ergo

y = e^((ln x)/3)

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