1. **State the problem:** We need to solve the equation $$p(x) = (x-2)(3x-4)(2x-5) = 5$$ for $x$.
2. **Rewrite the equation:** Set the product equal to 5:
$$ (x-2)(3x-4)(2x-5) = 5 $$
3. **Expand the product:** First, multiply two factors:
$$ (x-2)(3x-4) = 3x^2 -4x -6x +8 = 3x^2 -10x +8 $$
4. **Multiply the result by the third factor:**
$$ (3x^2 -10x +8)(2x-5) = 3x^2 \cdot 2x - 3x^2 \cdot 5 -10x \cdot 2x + 10x \cdot 5 + 8 \cdot 2x - 8 \cdot 5 $$
$$ = 6x^3 - 15x^2 - 20x^2 + 50x + 16x - 40 $$
5. **Combine like terms:**
$$ 6x^3 - 35x^2 + 66x - 40 $$
6. **Set equal to 5 and bring all terms to one side:**
$$ 6x^3 - 35x^2 + 66x - 40 = 5 $$
$$ 6x^3 - 35x^2 + 66x - 45 = 0 $$
7. **Solve the cubic equation:**
$$ 6x^3 - 35x^2 + 66x - 45 = 0 $$
This cubic can be solved by rational root theorem or numerical methods.
8. **Check possible rational roots:** Factors of 45 are $\pm1, \pm3, \pm5, \pm9, \pm15, \pm45$ and factors of 6 are $\pm1, \pm2, \pm3, \pm6$.
Possible rational roots are $\pm \frac{1}{1}, \pm \frac{1}{2}, \pm \frac{1}{3}, \pm \frac{1}{6}, \pm \frac{3}{1}, \pm \frac{3}{2}, \pm \frac{3}{3}, \pm \frac{3}{6}, \pm \frac{5}{1}, \pm \frac{5}{2}, \pm \frac{5}{3}, \pm \frac{5}{6}, \pm \frac{9}{1}, \pm \frac{9}{2}, \pm \frac{9}{3}, \pm \frac{9}{6}, \pm \frac{15}{1}, \pm \frac{15}{2}, \pm \frac{15}{3}, \pm \frac{15}{6}, \pm \frac{45}{1}, \pm \frac{45}{2}, \pm \frac{45}{3}, \pm \frac{45}{6}$.
9. **Test $x=3$:**
$$6(3)^3 - 35(3)^2 + 66(3) - 45 = 6(27) - 35(9) + 198 - 45 = 162 - 315 + 198 - 45 = 0$$
So, $x=3$ is a root.
10. **Divide the cubic by $(x-3)$:**
Using polynomial division or synthetic division:
$$6x^3 - 35x^2 + 66x - 45 \div (x-3) = 6x^2 - 17x + 15$$
11. **Solve the quadratic:**
$$6x^2 - 17x + 15 = 0$$
Use quadratic formula:
$$x = \frac{17 \pm \sqrt{(-17)^2 - 4 \cdot 6 \cdot 15}}{2 \cdot 6} = \frac{17 \pm \sqrt{289 - 360}}{12} = \frac{17 \pm \sqrt{-71}}{12}$$
12. **Interpret the result:** Since the discriminant is negative, the quadratic has no real roots.
13. **Final answer:** The only real solution is
$$\boxed{x = 3}$$
Solve Polynomial 01Fec2
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