1. **State the problem:** Simplify or factor the cubic polynomial $x^3 + 2x^2 - 5x - 6$.
2. **Formula and rules:** To factor a cubic polynomial, try to find rational roots using the Rational Root Theorem, then use polynomial division or synthetic division to factor.
3. **Find possible roots:** Possible rational roots are factors of the constant term $-6$: $\pm1, \pm2, \pm3, \pm6$.
4. **Test roots:** Substitute $x=1$:
$$1^3 + 2(1)^2 - 5(1) - 6 = 1 + 2 - 5 - 6 = -8 \neq 0$$
Substitute $x=2$:
$$2^3 + 2(2)^2 - 5(2) - 6 = 8 + 8 - 10 - 6 = 0$$
So, $x=2$ is a root.
5. **Divide polynomial by $(x-2)$:**
Using synthetic division:
\begin{align*}
&2 | 1 \quad 2 \quad -5 \quad -6 \\
&\quad \quad 2 \quad 8 \quad 6 \\
&\quad 1 \quad 4 \quad 3 \quad 0
\end{align*}
The quotient is $x^2 + 4x + 3$.
6. **Factor the quadratic:**
$$x^2 + 4x + 3 = (x + 1)(x + 3)$$
7. **Final factorization:**
$$x^3 + 2x^2 - 5x - 6 = (x - 2)(x + 1)(x + 3)$$
**Answer:** The polynomial factors as $(x - 2)(x + 1)(x + 3)$.
Cubic Factorization Ab5Cd4
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