1. **State the problem:** Solve the equation $$2x^{\frac{2}{3}} - x^{\frac{1}{3}} = 3$$ for $x$.
2. **Introduce substitution:** Let $y = x^{\frac{1}{3}}$. Then $x^{\frac{2}{3}} = y^2$.
3. **Rewrite the equation:** Substitute into the original equation:
$$2y^2 - y = 3$$
4. **Rearrange into standard quadratic form:**
$$2y^2 - y - 3 = 0$$
5. **Solve the quadratic equation:** Use the quadratic formula:
$$y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
where $a=2$, $b=-1$, and $c=-3$.
Calculate the discriminant:
$$\Delta = (-1)^2 - 4 \times 2 \times (-3) = 1 + 24 = 25$$
So,
$$y = \frac{1 \pm 5}{4}$$
6. **Find the two solutions for $y$:**
- $$y_1 = \frac{1 + 5}{4} = \frac{6}{4} = \frac{3}{2}$$
- $$y_2 = \frac{1 - 5}{4} = \frac{-4}{4} = -1$$
7. **Back-substitute to find $x$:** Recall $y = x^{\frac{1}{3}}$, so
$$x = y^3$$
Calculate each:
- $$x_1 = \left(\frac{3}{2}\right)^3 = \frac{27}{8}$$
- $$x_2 = (-1)^3 = -1$$
8. **Final answer:**
$$x = \frac{27}{8}, -1$$
These are the simplified real solutions to the equation.
Solve Cube Root D422Ee
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