text: Q:
  
  What's the reverse of Math Power (**) in Ruby?
  
  I was wondering how to get the inverse of power in Ruby?
  2 ** 4 # => 16
  
  and then I would like to get the inverse of it, and I'm not sure which operator to use
  16 ?? 2 # => 4
  
  A:
  
  The inverse of exponentiation is the logarithm. If ab = c, then logac = b.
  You can find logarithm functions in the Math module, specifically log() for base-e and log10() for base-10.
  To get a logarithm to a different base (say n), use the formula logNa = logxa/logxN, where x is a value such as e or 10.
  For your specific case:
  
  log216    =   loge16/loge2    =   Math.log(16) / Math.log(2)    =   4
  
  Whether you consider the explanation good because it expands your knowledge, or bad because you hated high school math, is entirely up to you :-)
  
  A:
  
  Math.log(16) / Math.log(2)
  
  