Solve the exponential equation

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Mathematics

1 answer:

Tom [10]3 years ago

5 0

$10^{-x}=7^{4x}\\
\ln 10^{-x}=\ln 7^{4x}\\
-x \ln 10=4x\ln 7\\
-x \ln 10-4x\ln 7=0\\
x(-\ln 10-4\ln 7)=0\\
x=0$

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