Last question PRECAL

We have been given the function
[tex]x^5-x^2-x+1[/tex]
The degree of this polynomial is 5.
We know that the maximum number of turning points of a function is one less the degree of the function.
Here, the degree of the function is 5.
Hence, from the above mentioned concept, the maximum number of turning points is given by
[tex]=5-1=4[/tex]
Hence, maximum number of turning points is 4.