Elementary Number Theory: Proving log$_2$($3$) is irrational using the Fundamental Theorem of Arithmetic.

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Problem: Prove $log$$_2$($3$) is irrational using the Fundamental Theorem of Arithmetic.

What I have so far:

Proof: Suppose $log$$_2$($3$) $\in$ $\mathbb Q$

Then there are $p,q$ $\in$ $\mathbb Z$ , $q$$\neq$$0$ s.t. $log$$_2$($3$)=$\frac pq$

Then $2$$^p$ $=$ $3$$^q$

This is where I get stuck because I'm not sure how to incorporate the Fundamental Theorem of Arithmetic.

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The fundamental theorem of arithmetic tells you that the prime factorisation of any positive integer is unique.

Applying this to the positive integer $n = 2^p = 3^q$, you see that $2^p$ and $3^q$ are two candidate prime factorisations for the same integer $n$.

The only way these prime factorisations can actually be the same is if $p = 0$ and $q = 0$. This is absurd, because $q \neq 0$.