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April 20, 2014

April 20, 2014

Posted by **Miley** on Friday, December 27, 2013 at 4:08pm.

f(n)= (n-1). if n is even;

f(n)= (2n). if n is odd.

If k ∈ N, and f (f (f(k))) = 21, find the sum of the digits in k

I really don't get this means. (∈)

- Math -
**Damon**, Friday, December 27, 2013 at 5:07pm"is an element of "

see:

http://www.glenoaks.edu/facultystaff/FacultyWebSites/JillToner/Documents/NSM105%20-%20Math%20for%20El%20Ed/Section%202.1%20-%20Set%20Theory.pdf

- Math -
**Damon**, Friday, December 27, 2013 at 5:26pmf [ f ( f(k) ) ] = 21

f ( f(k) ) = 22

f(k) = 11

k = 12

- Math -
**Damon**, Friday, December 27, 2013 at 5:27pmso about two digits in twelve

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