1. **State the problem:** Simplify the expression $$\frac{x^3 - 7x + 6}{x^2 + 4x - 5} \times \frac{x^2 + 9x + 20}{x^3 - 4x^2 + 5x - 2}$$.
2. **Factor each polynomial:**
- Numerator of first fraction: $$x^3 - 7x + 6$$.
Try to find roots by inspection or Rational Root Theorem.
Test $x=1$: $1^3 - 7(1) + 6 = 1 - 7 + 6 = 0$, so $(x-1)$ is a factor.
Divide $x^3 - 7x + 6$ by $(x-1)$:
$$\frac{x^3 - 7x + 6}{x-1} = x^2 + x - 6$$.
Factor $x^2 + x - 6$:
$$x^2 + x - 6 = (x+3)(x-2)$$.
So,
$$x^3 - 7x + 6 = (x-1)(x+3)(x-2)$$.
- Denominator of first fraction: $$x^2 + 4x - 5$$.
Factor:
$$x^2 + 4x - 5 = (x+5)(x-1)$$.
- Numerator of second fraction: $$x^2 + 9x + 20$$.
Factor:
$$x^2 + 9x + 20 = (x+5)(x+4)$$.
- Denominator of second fraction: $$x^3 - 4x^2 + 5x - 2$$.
Try to find roots:
Test $x=1$: $1 - 4 + 5 - 2 = 0$, so $(x-1)$ is a factor.
Divide by $(x-1)$:
$$\frac{x^3 - 4x^2 + 5x - 2}{x-1} = x^2 - 3x + 2$$.
Factor $x^2 - 3x + 2$:
$$x^2 - 3x + 2 = (x-1)(x-2)$$.
So,
$$x^3 - 4x^2 + 5x - 2 = (x-1)^2 (x-2)$$.
3. **Rewrite the expression with factors:**
$$\frac{(x-1)(x+3)(x-2)}{(x+5)(x-1)} \times \frac{(x+5)(x+4)}{(x-1)^2 (x-2)}$$
4. **Multiply the fractions:**
$$\frac{(x-1)(x+3)(x-2)(x+5)(x+4)}{(x+5)(x-1)(x-1)^2 (x-2)}$$
5. **Cancel common factors:**
- Cancel $(x-1)$ in numerator and denominator:
$$\frac{\cancel{(x-1)}(x+3)(x-2)(x+5)(x+4)}{(x+5)\cancel{(x-1)}(x-1)^2 (x-2)}$$
- Cancel $(x+5)$:
$$\frac{(x+3)(x-2)\cancel{(x+5)}(x+4)}{\cancel{(x+5)}(x-1)^2 (x-2)}$$
- Cancel $(x-2)$:
$$\frac{(x+3)\cancel{(x-2)}(x+4)}{(x-1)^2 \cancel{(x-2)}}$$
6. **Final simplified expression:**
$$\frac{(x+3)(x+4)}{(x-1)^2}$$
**Answer:** $$\boxed{\frac{(x+3)(x+4)}{(x-1)^2}}$$
Simplify Rational A65762
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