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Source: — Problem Solving |
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by Testluv » Mon Oct 26, 2009 4:16 pm
...1/x...

Just let x = a number and plug it in!
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by truplayer256 » Mon Oct 26, 2009 4:53 pm
if you want to do it the algebraic way, you can always do this:

(x-1)!/x!

We know that x! is equal to x*(x-1)*(x-2).. and so on.

(x-1)! is equal to (x-1)*(x-2)*(x-3).. and so on.

(x-1)*(x-2)*(x-3)*.../(x)*(x-1)*(x-2)*...=1/x.

I suggest using the plugging in the number method to solve this problem so one can visualize it better.
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