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Solve the exponential equation. Express the solution of natural logarithmic

Solve the exponential equation. Express the solution of natural logarithmic-example-1
User THIAGO DE BONIS
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1 Answer

25 votes
25 votes

3^(x+6)=8

Equations of this form are solved by first taking the natural logarithm (ln) of both sides. So:


\ln (3^(x+6))=\ln (8)

We now use the property of logarithms shown below:


\ln (a^b)=b\ln (a)

So, the equation becomes:


\begin{gathered} \ln (3^(x+6))=\ln (8) \\ (x+6)\ln (3)=\ln (8) \end{gathered}

Distributing the value ln(3), we get:


\begin{gathered} (x+6)\ln (3)=\ln (8) \\ \ln (3)x+6\ln (3)=\ln (8) \end{gathered}

Now, we solve for x:


\begin{gathered} \ln (3)x+6\ln (3)=\ln (8) \\ \ln (3)x=\ln (8)-6\ln (3) \\ x=(\ln (8)-6\ln (3))/(\ln (3)) \\ x=(\ln 8)/(\ln 3)-6 \end{gathered}

Looking at the answer choices,

D is the correct answer!

User Usuf
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