MHB 3.4.238 AP calculus exam Limits with ln

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The limit expression presented is analyzed for its behavior as h approaches 0. It is clarified that the correct limit should involve the natural logarithm of 4 rather than h, leading to the application of the derivative definition. The limit ultimately converges to the derivative of ln(x) at x=4, which is 1/4. Some participants express confusion about the divergence of the limit, while others emphasize the importance of correctly identifying the function and applying the derivative concept. The discussion highlights the relevance of understanding limits and derivatives in calculus.
karush
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Solve
$$\displaystyle\lim_{h\to 0}
\dfrac{\ln{(4+h)}-\ln{h}}{h}$$
$$(A)\,0\quad
(B)\, \dfrac{1}{4}\quad
(C)\, 1\quad
(D)\, e\quad
(E)\, DNE$$
The Limit diverges so the Limit Does Not Exist (E)ok the only way I saw that it diverges is by plotting
not sure what the rule is that observation would make ploting not needed

also I noticed these AP sample questions are getting a lot of views so thot I would continue to post more
 
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Check your limit expression again. Should be

$\displaystyle \lim_{h \to 0} \dfrac{\ln(4+h) - \color{red}{ \ln(4)}}{h}$
Recall the limit definition of a derivative ...

$\displaystyle f’(x) = \lim_{h \to 0} \dfrac{f(x+h)-f(x)}{h}$

let $x=4$

... try again.
 

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