number properties

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by cjb » Wed Feb 11, 2009 7:06 am
I get the same:

f(5x) = 1/(x^3)

f(x/5) = (5^6) / (x^3)

f(5x) / f(x/5) = 1/(5^6)


Only thing about this answer is it's not in terms of f(x), it's constant instead. But given that it is a constant, I don't see how you could write it in terms of f(x).
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by marcusking » Wed Feb 11, 2009 7:10 am
cjb wrote:I get the same:

f(5x) = 1/(x^3)

f(x/5) = (5^6) / (x^3)

f(5x) / f(x/5) = 1/(5^6)
Can you explain how you get from f(5x) to 1/(x^3). What happened to the 125 as the numerator?

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by cjb » Wed Feb 11, 2009 7:24 am
marcusking wrote:Can you explain how you get from f(5x) to 1/(x^3). What happened to the 125 as the numerator?
f(x) = 125 / (x^3)

=> f(5x) = 125 / ((5x)^3)

= 125 / (125x^3)

= 1 / (x^3)
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