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find the limit. lim(x→2) 1/(x + 2) 1/2 does not exist -∞ ∞

Question

find the limit.
lim(x→2) 1/(x + 2)
1/2
does not exist
-∞

Explanation:

Step1: Substitute x - value

Substitute \(x = 2\) into \(\frac{1}{x + 2}\).
\[
\frac{1}{2+2}
\]

Step2: Simplify the expression

\[
\frac{1}{4}
\]
However, we made a wrong - step above. When \(x\to2\), we should consider the behavior of the function \(y=\frac{1}{x + 2}\).
As \(x\to2\), the function \(y = \frac{1}{x+2}\) is well - defined at \(x = 2\).
We substitute \(x = 2\) into the function \(y=\frac{1}{x + 2}\).
\[y=\frac{1}{2+2}=\frac{1}{4}\]
If we consider the limit \(\lim_{x\to - 2}\frac{1}{x + 2}\), as \(x\to - 2^{+}\), \(x+2\to0^{+}\) and \(\frac{1}{x + 2}\to+\infty\), as \(x\to - 2^{-}\), \(x + 2\to0^{-}\) and \(\frac{1}{x+2}\to-\infty\), so \(\lim_{x\to - 2}\frac{1}{x + 2}\) does not exist. But here \(x\to2\).
We substitute \(x = 2\) into \(\frac{1}{x+2}\), we get \(\frac{1}{2 + 2}=\frac{1}{4}\). There is no option for \(\frac{1}{4}\) in the given choices. If we assume it is a mis - type and the limit is \(\lim_{x\to - 2}\frac{1}{x+2}\):
As \(x\to - 2^{+}\), \(x+2\) approaches \(0\) from the positive side. Let \(t=x + 2\), when \(x\to - 2^{+}\), \(t\to0^{+}\), and \(\frac{1}{x + 2}=\frac{1}{t}\to+\infty\). As \(x\to - 2^{-}\), \(t=x + 2\to0^{-}\), and \(\frac{1}{x + 2}=\frac{1}{t}\to-\infty\). Since the left - hand limit and the right - hand limit are not equal, \(\lim_{x\to - 2}\frac{1}{x+2}\) does not exist.

Answer:

Does not exist