Maximum number of possible extreme values for the function f(x)=x^4+x^3-7x^2-x+6

Polynomials of degree greater than 2 can have more than one max or min value. The largest possible number of minimum or maximum points is one less than the degree of the polynomial. The following examples illustrate several possibilities.

since the degree is 4
number of possible extreme values = 4 -1 = 3

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