1. **State the problem:** Find all zeros of the polynomial function $$f(x) = 3x^4 + 11x^3 + 11x^2 + x - 2$$ and list them from smallest to largest, including multiplicities.
2. **Recall the Rational Root Theorem:** Possible rational roots are factors of the constant term divided by factors of the leading coefficient. Here, factors of $-2$ are $\pm1, \pm2$ and factors of $3$ are $\pm1, \pm3$. Possible rational roots: $\pm1, \pm2, \pm\frac{1}{3}, \pm\frac{2}{3}$.
3. **Test possible roots by substitution or synthetic division:**
- Test $x=1$: $3(1)^4 + 11(1)^3 + 11(1)^2 + 1 - 2 = 3 + 11 + 11 + 1 - 2 = 24 \neq 0$
- Test $x=-1$: $3(-1)^4 + 11(-1)^3 + 11(-1)^2 + (-1) - 2 = 3 - 11 + 11 - 1 - 2 = 0$ so $x=-1$ is a root.
4. **Divide $f(x)$ by $(x+1)$ using synthetic division:**
$$\begin{array}{r|rrrrr}
-1 & 3 & 11 & 11 & 1 & -2 \\
& & -3 & -8 & -3 & 2 \\
\hline
& 3 & 8 & 3 & -2 & 0
\end{array}$$
Quotient: $3x^3 + 8x^2 + 3x - 2$
5. **Find roots of the cubic $3x^3 + 8x^2 + 3x - 2$:**
Possible rational roots: $\pm1, \pm2, \pm\frac{1}{3}, \pm\frac{2}{3}$.
- Test $x=\frac{1}{3}$:
$$3\left(\frac{1}{3}\right)^3 + 8\left(\frac{1}{3}\right)^2 + 3\left(\frac{1}{3}\right) - 2 = 3\cdot\frac{1}{27} + 8\cdot\frac{1}{9} + 1 - 2 = \frac{1}{9} + \frac{8}{9} + 1 - 2 = 1 + 1 - 2 = 0$$
So $x=\frac{1}{3}$ is a root.
6. **Divide the cubic by $(x - \frac{1}{3})$:**
Multiply divisor by 3 to avoid fractions: divide by $(3x - 1)$.
Synthetic division:
$$\begin{array}{r|rrrr}
\frac{1}{3} & 3 & 8 & 3 & -2 \\
& & 1 & 3 & 2 \\
\hline
& 3 & 9 & 6 & 0
\end{array}$$
Quotient: $3x^2 + 9x + 6$
7. **Solve quadratic $3x^2 + 9x + 6 = 0$ using quadratic formula:**
$$x = \frac{-9 \pm \sqrt{9^2 - 4 \cdot 3 \cdot 6}}{2 \cdot 3} = \frac{-9 \pm \sqrt{81 - 72}}{6} = \frac{-9 \pm \sqrt{9}}{6} = \frac{-9 \pm 3}{6}$$
8. **Calculate roots:**
- $$x = \frac{-9 + 3}{6} = \frac{-6}{6} = -1$$
- $$x = \frac{-9 - 3}{6} = \frac{-12}{6} = -2$$
9. **List all roots including multiplicities:**
- From step 3: $x = -1$
- From step 6 and 8: $x = \frac{1}{3}$, $x = -1$, $x = -2$
So roots are $-2$, $-1$ (twice), and $\frac{1}{3}$.
**Final answer:**
$$x = -2, -1, -1, \frac{1}{3}$$
Find Zeros F5F85A
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