Fibonacci Number Exercise

gistfile1.rb

def is_fibonacci?(i)
  fib_arr = [0, 1]

  while fib_arr[-1] <= i do
    next_num = (fib_arr[-1] + fib_arr[-2])
    fib_arr << next_num
  end
  	
  if fib_arr.include?(i)
    true
  else
    false
  
  end
end