MHB Limit of Function at x=0: Does Not Exist (DNE)

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The limit in question, as x approaches 0 for the expression (1/(7x) - 1/(e^(7x) - 1)), is evaluated to be infinite from both sides. Although the limit technically does not exist (DNE), the instructions specify to enter "I" for infinity. The confusion arises from interpreting the behavior of the function near zero, where both components diverge. Therefore, the correct answer based on the provided guidelines is "I."
josesalazmat
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hello
I have an exercise which says:

Evaluate the following limit. Enter -I if your answer is −∞, enter I if your answer is ∞, and enter DNE if the limit does not exist.

$$ limx→0[(1/(7x)−(1)/((e^(7x))−1)] $$ e power 7x

when I follow the graph for $$1/7x$$ the limit does not exist (goes to infinite for the right and -infinite for the left)it is the same for $$1/(((e^(7x))−1)$$

my answer is DNE but it is wrong

where is a mistake?

Thanks

Jose
 
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Let:

$$f(x)=\frac{\dfrac{1}{7x}-1}{e^{7x}-1}$$

We see that:

$$\lim_{x\to0^{-}}f(x)=\lim_{x\to0^{+}}f(x)=\infty$$

Technically, this limit does not exist, but given the instructions, I would answer with "I."
 
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