4.1)
\The function is 
Using first principle (limit definition of a derivative)
\

\
4.2)
\The function is 
Differentiate on each side with respect to x.
\
4.3)
\The function is 
Differentiate on each side with respect to x.
\Product rule of differentiate :

4.4)
\Step 1:
\The function is 
Differentiate on each side with respect to x.
\
Find number of turns.
\The differentiate function
is has greatest power is 2.
Hence, The graph of the function is 2 turns.
\Find maximum and minimum points.
\
Step 2:
\Graph:
\Graph the function 

Observe the graph:
\The number of turns is two.
\The maximum point is
The minimum point is
Solution:
\