Common Logarithm/Examples/0.236

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Example of Common Logarithm

The common logarithm of $0 \cdotp 236$ is:

$\log_{10} 0 \cdotp 236 = \overline 1 \cdotp 3729 = -0.6271$


Proof

\(\ds 0 \cdotp 236\) \(=\) \(\ds 2 \cdotp 36 \times 10^{-1}\) using scientific notation
\(\ds \leadsto \ \ \) \(\ds \log_{10} 0 \cdotp 236\) \(=\) \(\ds \map {\log_{10} } {2 \cdotp 36 \times 10^{-1} }\)
\(\ds \) \(=\) \(\ds \log_{10} 2 \cdotp 36 + \log_{10} 10^{-1}\) Logarithm of Product
\(\ds \) \(=\) \(\ds 0 \cdotp 3729 + \paren {-1}\) Common Logarithm of $2 \cdotp 36$, Definition of Common Logarithm
\(\ds \) \(=\) \(\ds \overline 1 \cdotp 3729\) Notation for Negative Logarithm
\(\ds \) \(=\) \(\ds -0.6271\)

$\blacksquare$


Sources