Solve the equation \(2^{3x-1} = 5(3^{1-x})\). Give your answer in the form \(\frac{\ln a}{\ln b}\) where \(a\) and \(b\) are integers.
Solution
Start by taking the natural logarithm of both sides of the equation:
\(\ln(2^{3x-1}) = \ln(5 \cdot 3^{1-x})\)
Apply the logarithm power rule: \(\ln(a^b) = b \ln a\).
\((3x-1)\ln 2 = \ln 5 + (1-x)\ln 3\)
Expand and rearrange the equation:
\(3x \ln 2 - \ln 2 = \ln 5 + \ln 3 - x \ln 3\)
Combine like terms:
\(3x \ln 2 + x \ln 3 = \ln 5 + \ln 3 + \ln 2\)
Factor out \(x\):
\(x(3 \ln 2 + \ln 3) = \ln 5 + \ln 3 + \ln 2\)
Solve for \(x\):
\(x = \frac{\ln 5 + \ln 3 + \ln 2}{3 \ln 2 + \ln 3}\)
Combine the logarithms:
\(x = \frac{\ln(5 \cdot 3 \cdot 2)}{\ln(2^3 \cdot 3)}\)
\(x = \frac{\ln 30}{\ln 24}\)
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