finding prime number

gistfile1.txt

def square_root (n)
	guess = n / 2.0
	while (((guess *guess) - n).abs > 0.000000001)
		guess = refine(guess, n)
	end
	return guess
end

def refine (guess, n)
	guess = (guess + (n / guess)) / 2.0
end

#checking for prime numbers
def prime (n)
	y = square_root (n)
	(2..y). each do |i|
		p = n % i 
		if p == 0 
			return
			false
		end
	end
	true
end

square_root (7)
puts prime (7)