Can you solve the equation 100! - 99!?

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The equation 100! - 99! simplifies to 99! * 99, as shown by substituting x for 99!. The breakdown reveals that 100! equals 100 times 99!, leading to the expression 100x - x, which simplifies to 99x. Further simplification is deemed unnecessary since calculating 99! directly is considered inefficient. The discussion highlights the limitations of factorial operations and the non-distributive nature of the factorial symbol. Ultimately, the solution confirms that 100! - 99! equals 99 times 99!.
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question: what is 100! - 99!

I've broken it down to a problem like this: Let x=99! Then 100! = 100*99! = 100x. 100x - x=99x = 99*99!.

I can't figure out a way to simplify the problem any more than that.

Thank you in advance for any help.
 
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There is the obvious: 100!- 99!= 99!(100- 1)= 99!(99).
 
you've got the right answer and I don't see how it COULD be simplified any further except by actually computing 99! which just seems like a waste of time.
 
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http://www.wolframalpha.com/input/?i=99*99!&dataset=

attachment.php?attachmentid=62587&stc=1&d=1381162058.gif


Edit: lol, too much time spent to attach the image.
 

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As is seen, "!" does not satisfy the distributive law for operations. :smile:
 
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