Ln vs. log in Short Calculus book by Serge Lang

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SUMMARY

The discussion centers on the derivative of the function a^x as presented in Serge Lang's "Short Calculus: The Original Edition of A First Course in Calculus." The book states that the derivative is a^x (log a), while contemporary sources assert it should be a^x (ln a). This discrepancy arises from the interpretation of "log" in the context of the book, which does not clarify that it refers to the natural logarithm (ln). The confusion is attributed to the book's publication date in 1964 and its lack of explicit mention of ln.

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  • Understanding of calculus, specifically derivatives.
  • Familiarity with logarithmic functions and their properties.
  • Knowledge of the difference between natural logarithm (ln) and common logarithm (log).
  • Basic comprehension of mathematical notation and terminology used in calculus texts.
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  • Research the historical context of mathematical texts, focusing on the evolution of logarithmic notation.
  • Study the properties and applications of natural logarithms (ln) versus common logarithms (log).
  • Explore derivative rules for exponential functions in various calculus textbooks.
  • Examine how different authors present logarithmic concepts in calculus literature.
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Homework Statement



I've been going through a book called "Short Calculus: The Original Edition of A First Course in Calculus," by Serge Lang. It says, " The derivative of a^x is a^x (log a)." But everything else I look at says the derivative of a^x is a^x (ln a). Since ln a and log a are different numbers, I don't see how both equations could be true. And, in fact, the Lang book never mentions ln at all!

The Lang book was 1st published in 1964 (although this is a 2002 printing). Could that be the explanation?


Homework Equations





The Attempt at a Solution

 
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If you write log_b(a) you mean log to the base b of a. If you just write log(a) that generally means log_e(a) which is the same as ln(a) as far as I know. What do you think log(a) means? I don't think Lang means log_10(a).
 
OK, I found it it, you're right. He just briefly mentions it at the end of the section. Confusing if you're new to it. Thanks.
 

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