five factorial
120
1*2*3*4*5
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5! = 120
Not that hard. Let's see now, how about this? (Simplify; no calculators now! And yes, the answer is a whole number.)
(5log(125))/(log(2.5) + log(2))
Last edited by Harakou (2011-06-05 22:44:20)
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Above.
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Hmm. Nope, wrong for me...
But 6! equals 3...
Anyways, it's 120. I read my sister's math book yesterday.
And before that I thought it was 240.
Last edited by Scratchthatguys (2011-06-05 22:46:09)
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Scratchthatguys wrote:
Hmm. Nope, wrong...
But 6! equals 3...
Anyways, it's 120. I read my sister's math book yesterday.
6! isn't three
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5! = 1*2*3*4*5
1*2=2*3=6*4=24*5=120
6! = 1*2*3*4*5*6
120
* 6
720
Last edited by scratch_yoshi (2011-06-05 22:46:39)
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Harakou wrote:
5! = 120
Not that hard. Let's see now, how about this? (Simplify; no calculators now! And yes, the answer is a whole number.)
(5log(125))/(log(2.5) + log(2))
I have no clue, whats log?

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Wouldn't that be infinite? Or would it go up?
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JJROCKER wrote:
Just wondering... is it possible to have a negative factorial? Like -3! ?
http://mathforum.org/library/drmath/view/60851.html
Nope, according to that a negative factorial would have an undefined value due to division by zero.
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Actually, if factorals included 0, they'd all equal zero, just pointing that out
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JJROCKER wrote:
Harakou wrote:
5! = 120
Not that hard. Let's see now, how about this? (Simplify; no calculators now! And yes, the answer is a whole number.)
(5log(125))/(log(2.5) + log(2))I have no clue, whats log?
log(x) is a logarithm of x with base 10. A logarithm is the inverse of a exponent. For a logarithm of x with base b and result a, b^a = x. So for example, log(100) = 2.
Of course, now that I posted that, I realized that it wasn't exactly the expression I intended. A better one that should be relatively easy to solve assuming you know the properties of logarithms would be this:
(125log(5))/(log(2.5) + log(2))
The basic properties are as follows:
log(a) + log(b) = log(ab)
log(a) - log (b) = log(a/b)
a * log(x) = log(x^a)
log (base b) of x = log(x)/log(b) (It's hard to express the base here because I don't have access to subscripts.)
Of course, I kinda feel like I'm intruding on your thread here. Not sure if you meant this as a specific discussion about factorials or a place to talk about mathematics in general and quiz each other.
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