Finding log something, in terms of A and B.

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Homework Statement



If Logb2=A and Logb49=B, what is logb397, in terms of A and B.

This is one of the bonus question in my geometric quiz and i don't remember if the number is 397. I wonder if anyone get this?

Homework Equations





The Attempt at a Solution


here is what i did
bA=2 and bB=49
b=21/A b=491/B
491/B=21/A --> log(49)/log(2)=B/A

because this is geometric quiz, so i assume this one have a geometric
so i use arn-1
r : log(49)/log(2)=B/A
a : log(2)

log(2)(B/A)n-1=logb397
am i right?
 
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