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Hello, I need some help with this precalculus question for my homework, please HW Q4

Hello, I need some help with this precalculus question for my homework, please HW-example-1
User Adrien Lamothe
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1 Answer

19 votes
19 votes

Answer:

The equation is given below as


2\log_2(x-3)+\log_22=3

Step 1:

Apply the logarithm law of exponents below


\begin{gathered} a\log_bx \\ =\log_bx^a \end{gathered}
\begin{gathered} 2\log_2(x-3) \\ =\log_2(x-3)^2 \end{gathered}
\begin{gathered} 2\operatorname{\log}_2(x-3)+\operatorname{\log}_22=3 \\ \log_2(x-3)^2+\operatorname{\log}_22=3 \end{gathered}

Step 2:

Apply the logarithm law of addition below


\log_aM+\log_aN=\log_aMN

By applying the law, we will have


\begin{gathered} \operatorname{\log}_2(x-3)^2+\log_22=3 \\ \log_22(x-3)^2=3 \end{gathered}

Step 3:

Apply the logarithm principle below


\begin{gathered} \log_aM=x \\ M=a^x \end{gathered}

By applying the principle, we will have


\begin{gathered} \operatorname{\log}_22(x-3)^2=3 \\ 2(x-3)^2=2^3 \\ 2(x-3)^2=8 \\ divide\text{ both sides by 2} \\ (2(x-3)^2)/(2)=(8)/(2) \\ (x-3)^2=4 \end{gathered}

Step 4:

Square root both sides and then add 3 to both sides


\begin{gathered} √((x-3)^2)=√(4) \\ x-3=2 \\ x-3+3=2+3 \\ x=5 \end{gathered}

Hence,

The solution set is


\Rightarrow\lbrace5\rbrace

User Liu Guanghua
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