Using the Remainder Theorem to Factor p(x)
To factor the polynomial p(x) = x^3 – 6x^2 + 11x – 6 using the remainder theorem, we first need to find potential rational roots. The remainder theorem states that if a polynomial f(x) is divided by x – c, the remainder of this division is equal to f(c). If f(c) = 0, then c is a root of the polynomial.
Step 1: Identify Potential Rational Roots
According to the Rational Root Theorem, possible rational roots can be found by taking the factors of the constant term (which is -6) and dividing them by the factors of the leading coefficient (which is 1). The factors of -6 are:
- ±1
- ±2
- ±3
- ±6
Step 2: Test Potential Roots
We will test these potential roots in the polynomial. Let’s start with x = 1:
p(1) = (1)^3 - 6(1)^2 + 11(1) - 6 = 1 - 6 + 11 - 6 = 0
Since p(1) = 0, x = 1 is a root.
Step 3: Factor Out the Root
Having confirmed that 1 is a root, we can use synthetic division to divide p(x) by x – 1:
1 | 1 -6 11 -6
| 1 -5 6
-------------------
1 -5 6 0
The result from synthetic division gives us:
p(x) = (x - 1)(x^2 - 5x + 6)
Step 4: Factor the Quadratic Expression
Next, we need to factor the quadratic x^2 – 5x + 6. This can be factored into:
x^2 - 5x + 6 = (x - 2)(x - 3)
Final Factorization
Thus, the complete factorization of the polynomial is:
p(x) = (x - 1)(x - 2)(x - 3)
In conclusion, we have successfully factored the polynomial p(x) = x^3 – 6x^2 + 11x – 6 completely as: