1. **State the problem:** Solve the equation $$p^{\frac{2}{3}} - 2p^{\frac{1}{3}} = 8$$ for $p$.
2. **Substitute:** Let $x = p^{\frac{1}{3}}$. Then $p^{\frac{2}{3}} = (p^{\frac{1}{3}})^2 = x^2$.
3. **Rewrite the equation:** Using substitution, the equation becomes:
$$x^2 - 2x = 8$$
4. **Bring all terms to one side:**
$$x^2 - 2x - 8 = 0$$
5. **Solve the quadratic equation:** Use the quadratic formula:
$$x = \frac{2 \pm \sqrt{(-2)^2 - 4 \cdot 1 \cdot (-8)}}{2 \cdot 1} = \frac{2 \pm \sqrt{4 + 32}}{2} = \frac{2 \pm \sqrt{36}}{2} = \frac{2 \pm 6}{2}$$
6. **Calculate the roots:**
- $x = \frac{2 + 6}{2} = \frac{8}{2} = 4$
- $x = \frac{2 - 6}{2} = \frac{-4}{2} = -2$
7. **Recall substitution:** $x = p^{\frac{1}{3}}$, so
$$p^{\frac{1}{3}} = 4 \quad \text{or} \quad p^{\frac{1}{3}} = -2$$
8. **Solve for $p$:** Cube both sides:
- If $p^{\frac{1}{3}} = 4$, then $p = 4^3 = 64$
- If $p^{\frac{1}{3}} = -2$, then $p = (-2)^3 = -8$
9. **Final answer:**
$$p = 64 \quad \text{or} \quad p = -8$$
Solve Power Equation
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