I thought $\log(n)$ was like $10^x = n$ and $\ln(n)$ was $e^x = n$. But when I do $\ln(80)$, it gives me the answer for $\log$. Why is that?
[Math] Why does Wolfram Alpha handle $\log$ and $\ln$ the same
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logarithmswolfram alpha
I thought $\log(n)$ was like $10^x = n$ and $\ln(n)$ was $e^x = n$. But when I do $\ln(80)$, it gives me the answer for $\log$. Why is that?
Best Answer
It's simply a matter of definitions.
In all fields, $\ln$ means the natural log, or log base $e$, so that $\ln n = x$ whenever $e^x = n$. In engineering (and high school), $\log$ usually means the common log, or log base $10$, so that $\log n = x$ whenever $10^x = n$.
However, it happens that in higher mathematics, the common log just isn't very important. So for convenience, mathematicians often use the notation $\log$ to represent the natural log. Wolfram Alpha does things the same way.