1. **State the problem:** We want to analyze the sign of the function $$f(x) = x^3 + 2x^2 - 13x + 10$$ by creating a sign chart.
2. **Find the roots of the polynomial:** To create a sign chart, first find the roots where $$f(x) = 0$$.
3. **Try rational root theorem candidates:** Possible rational roots are factors of 10 over factors of 1: $$\pm1, \pm2, \pm5, \pm10$$.
4. **Evaluate at candidates:**
- $$f(1) = 1 + 2 - 13 + 10 = 0$$, so $$x=1$$ is a root.
- Divide $$f(x)$$ by $$x-1$$:
$$f(x) = (x-1)(x^2 + 3x - 10)$$
5. **Factor quadratic:**
$$x^2 + 3x - 10 = (x+5)(x-2)$$
6. **Roots are:** $$x = 1, -5, 2$$.
7. **Sign chart intervals:**
- $$(-\infty, -5)$$
- $$(-5, 1)$$
- $$(1, 2)$$
- $$(2, \infty)$$
8. **Test signs in each interval:**
- For $$x < -5$$, pick $$x = -6$$:
$$f(-6) = (-6-1)(-6+5)(-6-2) = (-7)(-1)(-8) = -56 < 0$$
- For $$-5 < x < 1$$, pick $$x=0$$:
$$f(0) = (0-1)(0+5)(0-2) = (-1)(5)(-2) = 10 > 0$$
- For $$1 < x < 2$$, pick $$x=1.5$$:
$$f(1.5) = (1.5-1)(1.5+5)(1.5-2) = (0.5)(6.5)(-0.5) = -1.625 < 0$$
- For $$x > 2$$, pick $$x=3$$:
$$f(3) = (3-1)(3+5)(3-2) = (2)(8)(1) = 16 > 0$$
9. **Summary of sign chart:**
$$\begin{array}{c|cccccc}
x & -\infty & & -5 & & 1 & & 2 & & +\infty \\
f(x) & - & 0 & + & 0 & - & 0 & + \\\end{array}$$
10. **Interpretation:** The function is negative on $$(-\infty, -5)$$ and $$(1, 2)$$, positive on $$(-5, 1)$$ and $$(2, \infty)$$, and zero at $$x = -5, 1, 2$$.
**Final answer:** The sign chart for $$f(x) = x^3 + 2x^2 - 13x + 10$$ is as above with roots at $$-5, 1, 2$$ and alternating signs accordingly.
Sign Chart 3Babdb
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