Step 1:

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(a) \ \

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The function is \"\" . \ \

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Apply derivative on each side with respect to x .

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\"\"

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Product rule of derivatives : \"\"

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\"\".

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Derivative of the logarithmic function: \"\".

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Apply the power rule: \"\".

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\"\"

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To find the critical numbers of \"\", equate \"\" to zero.

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\"\"  

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The critical points are \"\"

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Step 2: \ \

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(b) The critical points are \"\" and the test intervals are \"\".

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Since logarithm function domain contains only positive values. \ \

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Interval Test Value Sign of \"\"Conclusion
\"\" \"\" \

\"\"

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Decreasing
\"\" \"\" \

\"\"

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Increasing
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Thus, The function is increasing on the interval \"\" and \ \

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The function is decreasing on the interval \"\".

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Step 3: \ \

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(c) Consider \"\". \ \

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Apply derivative on each side with respect to x .

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\"\"

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Find \"\": \ \

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\"\".

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If \"\" and \"\", then \"\" has local minimum at \"\".

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By the above definition \"\" has local minimum at \"\". \ \

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Step 4: \ \

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(d) \"\".

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Determination of concavity and inflection points : 

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Equate \"\" to zero.

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\"\"

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\"\".

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Thus, the inflection points are \"\" split the intervals into \"\" and \"\".

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Interval

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Test Value Sign of \"\"Concavity
\"\"\"\" \

\"\"

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Down
\"\" \"\" \

\"\"

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Up
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Thus, the graph is concave up in the interval \"\" and 

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The graph is concave down in the interval \"\".

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Step 5: \ \

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(e) Inflection point at \"\" : \ \

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\"\".

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Inflection point is  \"\".

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\"\"

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Minimum point is  \"\" .

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Maximum point is \"\" .