Log Identity Proofs: Simplifying a^{log_{b}(c)}=c^{log_{b}(a)}

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Homework Statement



[itex]a^{log_{b}(c)}=c^{log_{b}(a)}[/itex]


The Attempt at a Solution


Take [itex]log_{a}[/itex] of both sides:
[itex]log_{a}(a^{log_{b}(c)})=log_{a}(c^{log_{b}(a)})[/itex]

gives:
[itex]log_{b}c=log_{b}alog_{a}c[/itex]

Looks like one more step for the RHS. I sort of see that the RHS should become [itex]log_{b}c[/itex] and then we'll be done. But standard log laws don't seem to help me make this step. Please help with this step/explain why this is so?
 
K29 said:

Homework Statement



[itex]a^{log_{b}(c)}=c^{log_{b}(a)}[/itex]


The Attempt at a Solution


Take [itex]log_{a}[/itex] of both sides:
[itex]log_{a}(a^{log_{b}(c)})=log_{a}(c^{log_{b}(a)})[/itex]

gives:
[itex]log_{b}c=log_{b}alog_{a}c[/itex]

Looks like one more step for the RHS. I sort of see that the RHS should become [itex]log_{b}c[/itex] and then we'll be done. But standard log laws don't seem to help me make this step. Please help with this step/explain why this is so?
Using the commutative law of multiplication, the RHS is [itex]\displaystyle \ (\log_{a\,}c)\,(\log_{b\,}a)\quad\to\quad\log_{b\,}\left(a^{\log_{a\,}c}\right)[/itex]
 
Got it. Thanks a bunch
 

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