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For the function 5f(x)=x5ln(x), you can find critical points by setting the derivative equal to zero and solving for x. Then, determine the intervals (A,B] and [B,[infinity]) based on the critical points A and (B).

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Final Answer:

The critical points for the function
\(5f(x) = x^5 \ln(x)\) can be found by setting its derivative equal to zero. The intervals (A, B) and
\([B, \infty)\) are then determined based on the critical points A and B.

Step-by-step explanation:

To find the critical points, we need to find the derivative of
\(5f(x) = x^5 \ln(x)\). Let
\(g(x)\) be the derivative:


\[g(x) = (d)/(dx)(5x^5 \ln(x))\]

Applying the product rule and the chain rule, we get:


\[g(x) = 5 \cdot 5x^4 \ln(x) + 5x^5 \cdot (1)/(x)\]

Simplifying further:


\[g(x) = 25x^4 \ln(x) + 5x^4\]

Now, to find critical points, we set (g(x)) equal to zero and solve for (x):

\
[25x^4 \ln(x) + 5x^4 = 0\]

Factoring out
\(5x^4\), we get:


\[5x^4 (5 \ln(x) + 1) = 0\]

This equation gives two possible critical points: (x = 0) and
\(5 \ln(x) + 1 = 0\). However, (x = 0) is not in the domain of
\(\ln(x)\), so we only consider the second part.

Solving \
(5 \ln(x) + 1 = 0\) for (x), we find:


\[5 \ln(x) = -1\]


\[\ln(x) = -(1)/(5)\]


\[x = e^{-(1)/(5)}\]

So, the critical point is
\(x = e^{-(1)/(5)}\), and the intervals (A, B]) and
\([B, \infty)\) can be determined based on this critical point.

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