Step 1:

The function is .

Increasing-Decreasing Test:

1) If is increasing at .

2) If is decreasing at .

2) If is inconclusive at .

Apply derivative on each side with respect to .

Apply power rule of differentiation: .

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Step 2:

Find the function is increasing or decreasing at .

Substitute in .

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The function is increasing at .

Solution:

is increasing at .

(b)

The function is .

Apply derivative on each side with respect to .

Apply product rule in derivatives: .

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Step 2:

Find the function is increasing or decreasing at .

Substitute in .

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.

The function is not changing at .

Solution:

The function is not changing at . \ \

Step 2:

Find the critical points.

\

Find the critical number by equating to zero.

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