Answer:
d. x ∈ {-3, -2, 1}
Step-by-step explanation:
The word "approximate" in the problem statement suggests that the roots may not be integers. Consequently, the solution method of choice is graphing.
A graph shows the solutions to f(x)=0 to be x=-3, x=-2, and x=1, matching selection D.
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<em>Comment on the problem statement</em>
Any value of x can be put into the formula and it will be a "solution." For example, f(0) = -6 is a "solution" to the polynomial function. The problem statement is not specific as to the solution(s) sought. We have had to guess that we want values of x such that f(x)=0.
