Let the curve z(1+i)+zˉ(1−i)=4,z∈Cz(1+i) + \bar{z}(1-i) = 4, z \in \mathbb{C}, divide the region ∣z−3∣≤1|z-3| \leq 1 into two parts of areas α\alpha and β\beta. Then ∣α−β∣|\alpha - \beta| equals:

Answer: π2+1\frac{\pi}{2} + 1

Step-by-step solution

Step 1: Convert the complex equation to Cartesian form

We are given a complex equation for a curve. To understand its geometric representation, we substitute z=x+iyz = x + iy and zˉ=x−iy\bar{z} = x - iy into the equation. This allows us to convert the complex equation into its equivalent Cartesian form, which will reveal the type of curve.

Step 2: Simplify the equation to find the line

After substituting zz and zˉ\bar{z}, we expand the terms and combine the real and imaginary parts. The imaginary parts cancel out, leaving us with a linear equation in xx and yy. This equation, x−y=2x - y = 2, represents a straight line in the Cartesian plane.

Step 3: Identify the region and its properties

The region ∣z−3∣≤1|z-3| \leq 1 represents all complex numbers zz whose distance from the point 33 (which corresponds to (3,0)(3{,}0) in the Cartesian plane) is less than or equal to 11. This describes a closed disk centered at (3,0)(3{,}0) with a radius of 11. The total area of this disk is πr2=π(1)2=π\pi r^2 = \pi (1)^2 = \pi.

Step 4: Determine the relationship between the line and the circle

We need to find how the line x−y−2=0x - y - 2 = 0 intersects the circle (x−3)2+y2=1(x-3)^2 + y^2 = 1. We calculate the perpendicular distance dd from the center of the circle (3,0)(3{,}0) to the line. Since d=12≈0.707d = \frac{1}{\sqrt{2}} \approx 0.707 is less than the radius r=1r=1, the line intersects the circle, dividing it into two segments.

Step 5: Calculate the area of the smaller segment

The line divides the circle into two segments. The area of one segment (let's call it α\alpha) can be calculated using the formula for the area of a circular segment. We use the radius r=1r=1 and the distance d=1/2d = 1/\sqrt{2}. This gives us α=π4−12\alpha = \frac{\pi}{4} - \frac{1}{2}.

Step 6: Calculate the difference in areas

The total area of the disk is π\pi. If one part is α\alpha, the other part β\beta is π−α\pi - \alpha. We then find the absolute difference between α\alpha and β\beta. Substituting the value of α\alpha, we get the final result.

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