Select all of the following that are potential roots of [tex][tex]$p(x)=x^4-9x^2-4x+12$[/tex][/tex]:

A. [tex][tex]$ \pm 2 $[/tex][/tex]
B. [tex][tex]$ \pm 3 $[/tex][/tex]
C. [tex] \pm 6 [tex]$[/tex]
D. [tex] \pm 12 $[/tex][/tex]

Evaluate the function for the given values to determine if the value is a root:
[tex][tex]$ p(-2)=$[/tex][/tex] [tex][tex]$\square$[/tex][/tex]
[tex][tex]$ p(2)=$[/tex][/tex] [tex][tex]$\square$[/tex][/tex]

The value [tex][tex]$\square$[/tex][/tex] is a root of [tex][tex]$p(x)$[/tex][/tex].



Answer :

To determine whether a value is a root of the polynomial [tex]\( p(x) = x^4 - 9x^2 - 4x + 12 \)[/tex], we need to evaluate the polynomial at that value and check if the result is zero. A root of the polynomial is a value [tex]\( x \)[/tex] for which [tex]\( p(x) = 0 \)[/tex].

Let's evaluate the polynomial at the given values and see which evaluations yield zero.

1. Evaluate [tex]\( p(x) \)[/tex] at [tex]\( x = -2 \)[/tex]
[tex]\[ p(-2) = (-2)^4 - 9(-2)^2 - 4(-2) + 12 = \boxed{0} \][/tex]

2. Evaluate [tex]\( p(x) \)[/tex] at [tex]\( x = 2 \)[/tex]
[tex]\[ p(2) = 2^4 - 9 \cdot 2^2 - 4 \cdot 2 + 12 = \boxed{-16} \][/tex]

From these evaluations, we see that:
- [tex]\( p(-2) = 0 \)[/tex], indicating that [tex]\(-2\)[/tex] is a root of the polynomial.
- [tex]\( p(2) = -16 \)[/tex], indicating that [tex]\(2\)[/tex] is not a root of the polynomial.

Therefore, the value [tex]\(-2\)[/tex] is a root of [tex]\( p(x) \)[/tex].

To summarize, among the given options, [tex]\((\pm 2)\)[/tex] was initially considered:
- [tex]\(\pm 2\)[/tex] includes [tex]\(-2\)[/tex], which is a root of the polynomial.
- [tex]\(\pm 2\)[/tex] also includes [tex]\(2\)[/tex], which is not a root of the polynomial.

Thus, [tex]\(\pm 2\)[/tex] is partially correct. Specifically, only [tex]\(-2\)[/tex] is a root. The other provided values are not evaluated in this specific instruction, so no conclusion is drawn about them from this information alone.

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