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(1/3)^x=18 can you compute this

User MeltingDog
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1 Answer

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We have the following equation,


((1)/(3))^x=18

By taking logarithm base 3 to both sides, we have


\log _3((1)/(3))^x=\log _318

By the powers rule for logarithms, we get


x\cdot\log _3((1)/(3))^{}=\log _318

Now, by the quotient rule, we have that


\begin{gathered} \log _3((1)/(3))=\log _3(1)-\log _3(3) \\ \log _3((1)/(3))=-\log _3(3) \end{gathered}

because base 3 logarithm of 1 is zero. Then, we have


-x\cdot\log _3(3)^{}=\log _318

But


\log _3(3)=1

then, we obtain


-x=\log _318

By multiplying both sides by -1, we have


x=-\log _318

Finally, since


\log _318=2.6309

The answer is x= - 2.6309

User Criticalfix
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