Logarithm question
\(\large \color{black}{\begin{align} &If \hspace{.33em}\\~\\ &\dfrac13 \log_{3}M+3\log_{3}N=1+\log_{0.008} 5 \hspace{.33em}\\~\\ &then \hspace{.33em}\\~\\ &(1)\ \ M^{9}=\dfrac{9}{N} \hspace{.33em}\\~\\ &(2)\ \ N^{9}=\dfrac{9}{M} \hspace{.33em}\\~\\ &(3)\ \ M^{3}=\dfrac{3}{N} \hspace{.33em}\\~\\ &(4)\ \ N^{9}=\dfrac{3}{M} \hspace{.33em}\\~\\ \end{align}}\)
\(\large \color{black} \\~\\ \dfrac13 \log_{3}M+3\log_{3}N=1+\log_{0.008} 5 \\~\\ \log_{3}M^{1/3}+\log_{3}N^3=1+\log_{0.008} 5 \\~\\ \log_{3}\left( M^{1/3}\cdot N^3\right)=1+\log_{0.008} 5 \\~\\ \log_{3}\left( M^{1/3}\cdot N^3\right)=1+\log_{1/125} 5 \\~\\ \log_{3}\left( M^{1/3}\cdot N^3\right)=1+(-1/3) \\~\\ \log_{3}\left( M^{1/3}\cdot N^3\right)=2/3 \\~\\ \left( M^{1/3}\cdot N^3\right)=3^{2/3} \\~\\ \left( M^{1/3}\cdot N^3\right)^3=\left(3^{2/3} \right)^3\\~\\ M\cdot N^9 = 3^2 \)
well there's another way to solve this question @mathmath333
which one
the left side is easy to solve that yu would have done by the perls way.
for the write side log base(0.008) (5) you can write it as log base((0.2)^3) (5) which will equal to 1/3 * log base(0.2) 5 now 0.2 can be written as 1/5 that means 1/3 * [log base(1/5) 5] which in turns equals to 1/3 * [log 5/ (log(1/5))] which finally becomes 1/3 * [log 5/ (0-log5)] which gives -1/3
@mathmath333
right*
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