Is log4(18) an Irrational Number?

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SUMMARY

The discussion centers on proving that log4(18) is an irrational number. The user attempts to utilize the change of base formula, logab = logcb / logca, but struggles with the contradiction method necessary for the proof. The key conclusion is that log4(18) cannot be expressed as a fraction x/y, confirming its irrationality.

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Homework Statement


log418
rational numbers are in form x/y


Homework Equations


logab = logcb / logca


The Attempt at a Solution


log218 / log218 = x/y
(b) log218 = (a) log218
log218b = log218a

Then I am stuck.
 
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Sorry, the problem is prove that log(4)18 is irrational. I also realize that this should be done as a contradiction, I am just not sure how to do it.
 

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