Just solved it!
The computation is straightforward but tricky. You just need to take extra care not to make any careless mistake.
The periodic table is set to get a new addition say hello to the superheavy element ununseptium
There are 60 seconds in a minute. There are 60 minutes in an hour. And a day has twenty-four hours 12 hours of daylight and 12 hours night averaged through the year.
What makes the numbers 12 and 60 so special?
Please Tell me how I can show
We must prove that bothand . is clear since is a subset of .
To prove the other inclusion, supposeand let . . If we are done. If then, since , we have as well. In either case . Hence .
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Their forum: http://www.artofproblemsolving.com/Forum/index.php?