The correct function is
[tex] \\
\
f(x)=x^4+x^3-7x^2-x+6\\ [/tex]
The maximum number of possible extreme values for the function is determined by subtracting one from the degree of the polynomial.
where the degree of the polynomial should be greater than 2.
Here the degree of the polynomial is 4
Hence the maximum number of possible extreme values for the function is
4-1=3
