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Answer:
- 3
Step-by-step explanation:
Using the law of logarithms
[tex]log_{b}[/tex] x = n ⇔ x = [tex]b^{n}[/tex]
let [tex]log_{b}[/tex]( [tex]\frac{1}{b^3}[/tex]) = n
[tex]log_{b}[/tex]( [tex]b^{-3}[/tex]) = n, then
[tex]b^{-3}[/tex] = [tex]b^{n}[/tex]
Since bases are the same on both sides then equate the exponents
⇒ n = - 3 → (4)