The table shows the values of function [tex]$f$[/tex] at different values of [tex]$x$[/tex]. Determine which expressions are factors of this polynomial.

[tex]
f(x) = x^5 + x^4 - 27x^3 - x^2 + 146x - 120
[/tex]

\begin{tabular}{|c|c|}
\hline
[tex]$x$[/tex] & [tex]$f(x)$[/tex] \\
\hline
-5 & 0 \\
\hline
-4 & 240 \\
\hline
-3 & 0 \\
\hline
-1 & -240 \\
\hline
4 & 0 \\
\hline
5 & 960 \\
\hline
\end{tabular}

Select all the correct answers.

- [tex]x + 5[/tex]
- [tex]x - 5[/tex]
- [tex]x + 3[/tex]
- [tex]x - 3[/tex]
- [tex]x + 4[/tex]
- [tex]x - 4[/tex]



Answer :

To determine which expressions are factors of the polynomial [tex]\( f(x) = x^5 + x^4 - 27x^3 - x^2 + 146x - 120 \)[/tex], we consider the given values where [tex]\( f(x) \)[/tex] is zero. These are the points where the polynomial intersects the x-axis, effectively representing the roots of the polynomial.

The roots are:
- [tex]\( f(-5) = 0 \)[/tex]
- [tex]\( f(-3) = 0 \)[/tex]
- [tex]\( f(4) = 0 \)[/tex]

These roots correspond directly to the factors of the polynomial. For each root [tex]\( x = a \)[/tex], the factor is [tex]\( x - a \)[/tex].

1. For [tex]\( x = -5 \)[/tex]:
- The corresponding factor is [tex]\( x + 5 \)[/tex].

2. For [tex]\( x = -3 \)[/tex]:
- The corresponding factor is [tex]\( x + 3 \)[/tex].

3. For [tex]\( x = 4 \)[/tex]:
- The corresponding factor is [tex]\( x - 4 \)[/tex].

Thus, the expressions that are factors of the polynomial [tex]\( f(x) = x^5 + x^4 - 27x^3 - x^2 + 146x - 120 \)[/tex] are:

[tex]\[ x + 5, \quad x + 3, \quad x - 4 \][/tex]

Therefore, the correct answers are:

- [tex]\( x + 5 \)[/tex]
- [tex]\( x + 3 \)[/tex]
- [tex]\( x - 4 \)[/tex]