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Let $$C$$ be the set of all complex numbers. Let
$$S_1 = \{z \in C \mid |z - 3 - 2i|^2 = 8\}$$,
$$S_2 = \{z \in C \mid \text{Re}(z) \geq 5\}$$ and
$$S_3 = \{z \in C \mid |z - \bar{z}| \geq 8\}$$.
Then the number of elements in $$S_1 \cap S_2 \cap S_3$$ is equal to
Let a general complex number be written as $$z = x + iy$$ where $$x = \text{Re}(z)$$ and $$y = \text{Im}(z)$$. We now translate the three set-descriptions into algebraic conditions in $$x$$ and $$y$$ so that we can see their mutual intersection clearly.
From $$S_1$$ we have
$$|z - (3 + 2i)|^2 = 8.$$
Using the fact that $$|a + ib|^2 = a^2 + b^2$$, we write
$$|(x+iy) - (3 + 2i)|^2 = |(x-3) + i(y-2)|^2 = (x-3)^2 + (y-2)^2.$$
So the condition for $$S_1$$ becomes
$$ (x-3)^2 + (y-2)^2 = 8. \quad -(1)$$
This is the equation of a circle with centre $$(3,\,2)$$ and radius $$\sqrt{8} = 2\sqrt2 \;(\approx 2.828).$$
From $$S_2$$ we are told that the real part is at least $$5$$, so
$$\text{Re}(z) \ge 5 \quad\Longrightarrow\quad x \ge 5. \quad -(2)$$
For $$S_3$$ we use the conjugate. Because $$\bar z = x - iy$$, we have
$$z - \bar z = (x + iy) - (x - iy) = 2iy.$$
Now, $$|2iy| = 2|y|,$$ therefore the condition $$|z - \bar z|\ge 8$$ gives
$$2|y| \ge 8 \quad\Longrightarrow\quad |y| \ge 4 \quad\Longrightarrow\quad y \ge 4 \text{ or } y \le -4. \quad -(3)$$
We now want the simultaneous satisfaction of (1), (2) and (3). In other words, we need all points on the circle (1) that also lie in the half-plane $$x\ge 5$$ and simultaneously have either $$y\ge 4$$ or $$y\le -4$$.
Because the circle’s centre is $$(3,2)$$ and its radius is $$2\sqrt2\approx 2.828,$$ its extreme $$x$$-coordinates are
$$x_{\min}=3-2\sqrt2\approx 0.172,\qquad x_{\max}=3+2\sqrt2\approx5.828.$$
Condition (2) restricts us to
$$5 \le x \le 5.828. \quad -(4)$$
Let us keep $$x$$ within the interval (4) and solve (1) for $$y$$. Starting from (1), we isolate the $$y$$-part:
$$ (y-2)^2 = 8 - (x-3)^2. $$
Taking the square root of both sides gives
$$ y - 2 = \pm\sqrt{\,8 - (x-3)^2\,}. \quad -(5)$$
Define
$$t = \sqrt{\,8 - (x-3)^2\,}, \qquad t\ge 0.$$
Then the two possible $$y$$ values are
$$ y = 2 + t \quad\text{or}\quad y = 2 - t. \quad -(6)$$
We next impose (3). First consider $$y \ge 4.$$ Using (6) we have
$$2 + t \ge 4 \quad\Longrightarrow\quad t \ge 2. \quad -(7)$$
Because $$t=\sqrt{\,8 - (x-3)^2\,},$$ inequality (7) squares to
$$8 - (x-3)^2 \ge 4 \quad\Longrightarrow\quad (x-3)^2 \le 4. \quad -(8)$$
Inequality (8) is the same as
$$-2 \le x - 3 \le 2 \quad\Longrightarrow\quad 1 \le x \le 5. \quad -(9)$$
Combining (9) with the earlier restriction (4), we must have
$$5 \le x \le 5.828\quad\text{and}\quad 1 \le x \le 5.$$
The only common value is
$$x = 5.$$
Substituting $$x=5$$ back into (1) to find $$y$$, we compute
$$(x-3)^2 = (5-3)^2 = 4,$$
and hence
$$(y-2)^2 = 8 - 4 = 4.$$
Therefore
$$y - 2 = \pm 2 \quad\Longrightarrow\quad y = 4 \ \text{or}\ y = 0.$$
From (3) we need $$|y| \ge 4,$$ so $$y = 0$$ is discarded while $$y = 4$$ is accepted.
We must also test the case $$y \le -4$$. However, the circle’s lowest $$y$$-coordinate is the centre coordinate minus the radius, namely $$2 - 2\sqrt2 \approx -0.828,$$ which is already greater than $$-4.$$ Thus no point on the circle can satisfy $$y\le -4.$$
Consequently, exactly one point survives all three conditions, namely
$$z = 5 + 4i.$$
There is only one such complex number, so the intersection $$S_1 \cap S_2 \cap S_3$$ contains exactly one element.
Hence, the correct answer is Option A.
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