(a)

Observe the derivative graph:

From the first derivative test if

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positive on the interval

\"\"

, then the function

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increases on the interval

\"\"

The graph

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is increasing on

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since

\"\"

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The graph $\"\"$ is decreasing on $\"\"$ since $\"\"$ on $\"\"$ .

The graph $\"\"$ is again increasing on $\"\"$ since $\"\"$ on $\"\"$ .

The graph $\"\"$ is again decreasing on $\"\"$ since $\"\"$ on $\"\"$ .

$\"\"$

(b)

Use first derivative test to identify all relative extrema.

$\"\"$ changes from positive to negative at $\"\"$ .

Therefore according to first derivative test , the function has maximum at $\"\"$ .

$\"\"$ changes from negative to positive at $\"\"$ .

Therefore according to first derivative test , the function has minimum at $\"\"$ .

$\"\"$ changes from positive to negative at $\"\"$ .

Therefore according to first derivative test , the function has maximum at $\"\"$ .

(a) Increasing on

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and

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Decreasing on

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and

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(b) Relative minimum at

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Relative maximum at

\"\"

and

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