(a)

Observe the derivative graph:

From the first derivative test if

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positive on the interval

\"\"

, then the function

\"\"

increases on the interval

\"\"

The graph

\"\"

is increasing on

\"\"

since

\"\"

\"\"

The graph

\"\"

is decreasing on

\"\"

since

\"\"

\"\"

The graph

\"\"

is again increasing on

\"\"

since

\"\"

\"\"

$\"\"$

(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 $\"\"$ .

(a) Increasing on

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and

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Decreasing on

\"\"

(b) Relative minimum at

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Relative maximum at

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