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Let P = {z in : |z + 2 – 3i | le 1} and ...

Let `P = {z in : |z + 2 – 3i | le 1}` and `Q = {z in C : z (1 + i) + overline z (1 – i) le –8}` . Let in `P cap Q`, `|z – 3 + 2i|` be maximum and minimum at `z_1` and `z_2` respectively. If `|z_1|^2 + 2|z_2|^2 = alpha + beta sqrt 2` , where `alpha , beta` are integers, then `alpha + beta` equals ________.

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To solve the problem, we need to analyze the sets \( P \) and \( Q \) and find the intersection \( P \cap Q \). We will then determine the points \( z_1 \) and \( z_2 \) where \( |z - (3 - 2i)| \) is maximized and minimized, respectively. Finally, we will compute \( |z_1|^2 + 2|z_2|^2 \) and express it in the form \( \alpha + \beta \sqrt{2} \). ### Step 1: Define the set \( P \) The set \( P \) is defined as: \[ P = \{ z \in \mathbb{C} : |z + 2 - 3i| \leq 1 \} \] This represents a circle in the complex plane with center at \( (-2, 3) \) and radius \( 1 \). ### Step 2: Define the set \( Q \) The set \( Q \) is defined as: \[ Q = \{ z \in \mathbb{C} : z(1 + i) + \overline{z}(1 - i) \leq -8 \} \] Let \( z = x + iy \). Then, \( \overline{z} = x - iy \). Substituting these into the inequality gives: \[ (x + iy)(1 + i) + (x - iy)(1 - i) \leq -8 \] Expanding this: \[ (x + iy + ix - y) + (x - iy - ix - y) \leq -8 \] Combining like terms: \[ 2x - 2y \leq -8 \implies x - y \leq -4 \] This represents a line in the complex plane. ### Step 3: Find the intersection \( P \cap Q \) We need to find the points where the circle defined by \( P \) intersects with the line defined by \( Q \). The equation of the circle is: \[ (x + 2)^2 + (y - 3)^2 \leq 1 \] And the equation of the line is: \[ x - y = -4 \implies y = x + 4 \] ### Step 4: Substitute the line equation into the circle equation Substituting \( y = x + 4 \) into the circle equation: \[ (x + 2)^2 + ((x + 4) - 3)^2 \leq 1 \] This simplifies to: \[ (x + 2)^2 + (x + 1)^2 \leq 1 \] Expanding both squares: \[ (x^2 + 4x + 4) + (x^2 + 2x + 1) \leq 1 \] Combining like terms: \[ 2x^2 + 6x + 5 \leq 1 \implies 2x^2 + 6x + 4 \leq 0 \] Dividing by 2: \[ x^2 + 3x + 2 \leq 0 \] Factoring: \[ (x + 1)(x + 2) \leq 0 \] The roots are \( x = -1 \) and \( x = -2 \). The solution is: \[ -2 \leq x \leq -1 \] ### Step 5: Find corresponding \( y \) values Using \( y = x + 4 \): - For \( x = -2 \), \( y = -2 + 4 = 2 \) → Point \( z_1 = -2 + 2i \) - For \( x = -1 \), \( y = -1 + 4 = 3 \) → Point \( z_2 = -1 + 3i \) ### Step 6: Calculate \( |z_1|^2 \) and \( |z_2|^2 \) Calculating \( |z_1|^2 \): \[ |z_1|^2 = |-2 + 2i|^2 = (-2)^2 + (2)^2 = 4 + 4 = 8 \] Calculating \( |z_2|^2 \): \[ |z_2|^2 = |-1 + 3i|^2 = (-1)^2 + (3)^2 = 1 + 9 = 10 \] ### Step 7: Compute \( |z_1|^2 + 2|z_2|^2 \) Now we compute: \[ |z_1|^2 + 2|z_2|^2 = 8 + 2 \times 10 = 8 + 20 = 28 \] ### Step 8: Express in the form \( \alpha + \beta \sqrt{2} \) We need to express \( 28 \) in the form \( \alpha + \beta \sqrt{2} \). Here, \( \alpha = 28 \) and \( \beta = 0 \). Thus, \( \alpha + \beta = 28 + 0 = 28 \). ### Final Answer \[ \boxed{28} \]
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