To determine the remaining linear factors of the polynomial \( 4x^4 - 20x^3 + 23x^2 + 5x - 6 \) given the known factors \( (x - 3) \) and \( (x - 2) \), we can use polynomial division or synthetic division to divide the polynomial by the factors \( (x - 3) \) and \( (x - 2) \).
Step 1: Synthetic Division by \( (x - 3) \)
We start by dividing the polynomial by \( (x - 3) \):
- Write down the coefficients: \( 4, -20, 23, 5, -6 \).
- Set up synthetic division. We will use \( 3 \) as the value.
\[ \begin{array}{r|rrrrr} 3 & 4 & -20 & 23 & 5 & -6 \ & & 12 & -24 & -3 & 6 \ \hline & 4 & -8 & -1 & 2 & 0 \ \end{array} \]
The resulting polynomial is \( 4x^3 - 8x^2 - x + 2 \).
Step 2: Synthetic Division by \( (x - 2) \)
Now we divide \( 4x^3 - 8x^2 - x + 2 \) by \( (x - 2) \):
- Set up synthetic division again with the coefficients \( 4, -8, -1, 2 \) and the value \( 2 \).
\[ \begin{array}{r|rrrr} 2 & 4 & -8 & -1 & 2 \ & & 8 & 0 & -2 \ \hline & 4 & 0 & -1 & 0 \ \end{array} \]
The resulting polynomial is \( 4x^2 - 1 \).
Step 3: Factor the Remaining Polynomial
Now we have \( 4x^2 - 1 \). This can be factored further as a difference of squares:
\[ 4x^2 - 1 = (2x - 1)(2x + 1) \]
Conclusion
So, the complete factorization of the given polynomial \( 4x^4 - 20x^3 + 23x^2 + 5x - 6 \) is:
\[ (x - 3)(x - 2)(2x - 1)(2x + 1) \]
Thus, the remaining linear factors of the polynomial are \( (2x - 1) \) and \( (2x + 1) \).