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If limx→a f(x) exists, then so do limx→a- f(x) and limx→a+ f(x).​

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Answer: If the limit of a function f(x) exists as x approaches a, then both the left-hand limit (limx→a- f(x)) and the right-hand limit (limx→a+ f(x)) also exist.

Explanation:

1. To understand why this is true, let's start with the definition of a limit. The limit of f(x) as x approaches a, denoted as limx→a f(x), represents the value that f(x) approaches as x gets arbitrarily close to a.

2. The left-hand limit (limx→a- f(x)) represents the value that f(x) approaches as x approaches a from the left side, or values of x that are smaller than a. This is the limit as x gets arbitrarily close to a but from values smaller than a.

3. Similarly, the right-hand limit (limx→a+ f(x)) represents the value that f(x) approaches as x approaches a from the right side, or values of x that are larger than a. This is the limit as x gets arbitrarily close to a but from values larger than a.

4. Since the limit of f(x) exists as x approaches a, it means that f(x) approaches a unique value as x gets arbitrarily close to a. This implies that both the left-hand limit and the right-hand limit must also approach the same unique value.

5. Therefore, if limx→a f(x) exists, then both limx→a- f(x) and limx→a+ f(x) also exist and have the same value.

In summary, if the limit of a function f(x) exists as x approaches a, then the left-hand limit and the right-hand limit of f(x) also exist and have the same value.

I hope this helps :)

User Maxim Filatov
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