+0  
 
0
634
1
avatar

As you know, one way to calculate "e" is this very simple exponential formula:

(1 + 1/n)^n. For large n, such as 10^6, the number of accurate digits of e is proportional to the exponent, or 6 accurate digits in this case. But, when you use n + 1/2 as an exponent (or 1,000,000.5 in this case), the number of accurate digits of e goes up as 2n, or twice as many accurate digits of e!!. The question is: why? Appreciate any insights. Many thanks.

 Dec 4, 2015
 #1
avatar+495 
0

I just played with my calculator and I see exactly what you're talking about.

 

Basically what you're saying is: instead of (1+1/n)^n, doing (1+1/n)^(n+0.5) gives you more accurate digits.

 

(1+1/100)^100 = 2.7048...

(1+1/100)^100.5 = 2.7183 ...  (exactly 2x more accurate digits)

 

(1+1/1000)^1000 = 2.7169239 ...

(1+1/1000)^1000.5 = 2.71828205... (again 2x more accurate digits)

 

It's pretty interesting, but I don't know why it would give you more accurate digits. Maybe it is a coincidence?

 Dec 4, 2015
edited by LambLamb  Dec 4, 2015

1 Online Users