Hello, nath_quam!
What do the graphs looks like and what are their key points?
\; P(x) \:= \<img src=)
1-x)^3(x-3)" alt="b)\; P(x) \:= \

1-x)^3(x-3)" />
has x-intercepts: 
As
. . . The graph rises to the right.
As
. . . The graph rises to the left.
You should be able to sketch the graph now . . .
Code:
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----o-------o-----o---------------o--
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| You can use the derivative to locate the exact positions
. . of the maximum and the two minimums.
1-x)^3(x-3)" alt="b)\;\;P(x)\:=\
1-x)^3(x-3)" /> has x-intercepts: 
The graph rises to the right and to the left.
We find that
is an inflection point
. . and there is a minimum at 
Code:
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--------+---o--------------o---
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