1. **Stating the problem:**
We are given the quadratic equation in $x$:
$$3x^2 - 2(2a + b)x + 2a^2 + 2ab + b^2 - 1 = 0,$$
with conditions:
(1) $a^2 + ab + b^2 \leq \frac{3}{2}$ and (2) $a + b \leq \sqrt{2}$.
2. **Understanding the problem:**
We want to analyze this quadratic equation and the given inequalities involving $a$ and $b$. The equation is quadratic in $x$ with coefficients depending on $a$ and $b$.
3. **Formula used:**
For a quadratic equation $Ax^2 + Bx + C = 0$, the discriminant is:
$$\Delta = B^2 - 4AC,$$
which determines the nature of roots.
4. **Identify coefficients:**
$$A = 3,$$
$$B = -2(2a + b) = -4a - 2b,$$
$$C = 2a^2 + 2ab + b^2 - 1.$$
5. **Calculate the discriminant:**
$$\Delta = B^2 - 4AC = (-4a - 2b)^2 - 4 \cdot 3 \cdot (2a^2 + 2ab + b^2 - 1).$$
6. **Simplify the discriminant:**
$$(-4a - 2b)^2 = 16a^2 + 16ab + 4b^2,$$
$$4 \cdot 3 \cdot (2a^2 + 2ab + b^2 - 1) = 12(2a^2 + 2ab + b^2 - 1) = 24a^2 + 24ab + 12b^2 - 12.$$
So,
$$\Delta = (16a^2 + 16ab + 4b^2) - (24a^2 + 24ab + 12b^2 - 12) = 16a^2 + 16ab + 4b^2 - 24a^2 - 24ab - 12b^2 + 12.$$
7. **Combine like terms:**
$$\Delta = (16a^2 - 24a^2) + (16ab - 24ab) + (4b^2 - 12b^2) + 12 = -8a^2 - 8ab - 8b^2 + 12.$$
8. **Factor out -8:**
$$\Delta = -8(a^2 + ab + b^2) + 12.$$
9. **Use inequality (1):**
Since $a^2 + ab + b^2 \leq \frac{3}{2}$,
$$\Delta \geq -8 \cdot \frac{3}{2} + 12 = -12 + 12 = 0.$$
This means the discriminant is non-negative, so the quadratic has real roots.
10. **Interpret inequality (2):**
$a + b \leq \sqrt{2}$ restricts the sum of $a$ and $b$.
11. **Summary:**
- The quadratic equation has real roots because $\Delta \geq 0$ under the given conditions.
- The conditions restrict $a$ and $b$ to a region where the quadratic behaves predictably.
12. **Additional note:**
The relation $AB^2 = AE \cdot AD$ and the description of the graph as a circle-like emblem suggest a geometric interpretation, possibly involving lengths in a circle or ellipse, but more context is needed for detailed analysis.
**Final answer:**
The quadratic equation has real roots for $x$ under the given conditions on $a$ and $b$ because the discriminant
$$\Delta = -8(a^2 + ab + b^2) + 12 \geq 0.$$
Quadratic Discriminant
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