/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 77 Is \(f(x)=\frac{x^{2}-5 x+6}{x-2... [FREE SOLUTION] | 91Ó°ÊÓ

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Is \(f(x)=\frac{x^{2}-5 x+6}{x-2}\) differentiable at \(x=2 ?\) Justify your answer.

Short Answer

Expert verified
Explain. Answer: The function is not differentiable at \(x=2\), because it is not continuous at that point.

Step by step solution

01

Check the continuity of the function at \(x=2\)

We need to find the limit of the function as \(x\) approaches 2. If this limit exists and is equal to the function value at \(x=2\), then the function is continuous at \(x=2\). Otherwise, the function is not continuous at \(x=2\). The function is given by \(f(x) = \frac{x^{2}-5 x+6}{x-2}\). Factor the numerator: \(x^{2}-5 x+6 = (x-2)(x-3)\). Then, the function can be written as $$f(x) = \frac{(x-2)(x-3)}{x-2}$$ which simplifies to $$f(x) = \begin{cases} x-3 & \text{if } x \neq 2 \\ \text{undefined} & \text{if } x=2 \end{cases} $$ Now, we find the limit as \(x\) approaches 2: $$\lim_{x \to 2} f(x) = \lim_{x \to 2} (x-3) = 2 - 3 = -1$$ As \(f(2)\) is undefined but the limit exists, the function is not continuous at \(x=2\).
02

Conclusion

Since the function is not continuous at \(x=2\), it is not differentiable at \(x=2\).

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