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Evaluate the limit, if it exists. (If an answer does not exist, enter DNE.)

lim x→−9 (1/9 + 1/x) / (9 + x)

User Waruyama
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1 Answer

6 votes

Final answer:

The limit as x approaches -9 of the given expression is -1/81 after simplifying and cancelling terms; there is no division by zero, so the limit exists.

Step-by-step explanation:

We are tasked to evaluate the limit as x approaches -9 of the following expression:

\(\lim_{x\to -9}\frac{\frac{1}{9} + \frac{1}{x}}{9+x}\)

Let's start by simplifying the expression inside the limit:

\(\frac{1}{9} + \frac{1}{x} = \frac{x+9}{9x}\)

The limit now becomes:

\(\lim_{x\to -9}\frac{x+9}{9x(9+x)}\)

Cancelling out the (x+9) terms, we get:

\(\lim_{x\to -9}\frac{1}{9x}\)

The direct answer in 2 lines would be:

Plugging in x = -9:

\(\frac{1}{9(-9)} = -\frac{1}{81}\)

Since the expression simplifies to a fraction with no division by zero, the limit exists and is equal to -1/81.

User Saroj Raut
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