Question

Prove that the mumtiple derieve frequency formula both in closed and open organ pipies

Answer 1

If you start with the same fundamental frequency for both open and closed, say f0f0, you'll notice that for the Open pipe, the harmonics are:

f0,2f0,3f0,...f0,2f0,3f0,...

While for the closed, 

f0,3f0,5f0,...f0,3f0,5f0,...

And you'll notice that the closed pipe has greater spacing of harmonics compared to the open pipe. 
That is for a given single note. You have to lower the note of the closed pipe by 12f012f0 (1 octave) to produce the same spacing of harmonics as the open pipe.