Problem

$\lim _{x \rightarrow 5} \frac{x+2}{x^{2}-5}$

Answer

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Answer

Final Answer: The limit of the function as x approaches 5 is \(\boxed{-\frac{1}{8}}\).

Steps

Step 1 :We are given the function \(f(x) = \frac{x+2}{x^{2}-5}\) and we are asked to find the limit as x approaches 5.

Step 2 :Substituting x=5 into the function, we get a division by zero, which is undefined. Therefore, we need to simplify the function first.

Step 3 :The denominator is a difference of squares, which can be factored into \((x-\sqrt{5})(x+\sqrt{5})\). However, the numerator does not contain these factors, so we cannot simplify the function by factoring.

Step 4 :Therefore, we need to use L'Hopital's rule, which states that the limit of a quotient of two functions as x approaches a certain value is equal to the limit of the quotients of their derivatives.

Step 5 :Taking the derivative of the numerator, we get 1. Taking the derivative of the denominator, we get -2x.

Step 6 :Substituting these into the function, we get \(f'(x) = \frac{1}{-2x}\).

Step 7 :Substituting x=5 into this function, we get \(-\frac{1}{10}\).

Step 8 :Final Answer: The limit of the function as x approaches 5 is \(\boxed{-\frac{1}{8}}\).

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