1. **State the problem:** Solve the exponential equation $$2^{2x} - 2^x - 12 = 0$$ for $x$.
2. **Rewrite the equation:** Notice that $2^{2x} = (2^x)^2$. Let $y = 2^x$. Then the equation becomes:
$$y^2 - y - 12 = 0$$
3. **Solve the quadratic equation:** Use the quadratic formula:
$$y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}$$
where $a=1$, $b=-1$, and $c=-12$.
4. **Calculate the discriminant:**
$$\sqrt{(-1)^2 - 4 \times 1 \times (-12)} = \sqrt{1 + 48} = \sqrt{49} = 7$$
5. **Find the roots:**
$$y = \frac{1 \pm 7}{2}$$
6. **Evaluate each root:**
- For $y = \frac{1 + 7}{2} = \frac{8}{2} = 4$
- For $y = \frac{1 - 7}{2} = \frac{-6}{2} = -3$
7. **Check for valid solutions:** Since $y = 2^x$ and $2^x > 0$ for all real $x$, discard $y = -3$.
8. **Solve for $x$:**
$$2^x = 4$$
Since $4 = 2^2$, we have:
$$2^x = 2^2$$
Therefore:
$$x = 2$$
**Final answer:**
$$x = 2$$
Exponential Equation 57Dfda
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