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Given that there are two distinct complex numbers z that satisfy =2r ∩ {z:arg(z-2)=3π/4} determine the exact range of values for the real constant r.

User Stan Smith
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Final answer:

To find the range of values for the real constant r, we need to solve the two given equations: |z-3-5i| = 2r and arg(z-2) = 3π/4. By solving these equations and simplifying, we find that the range of values for r is (-∞, +∞).

Step-by-step explanation:

To find the range of values for the real constant r, we need to solve the two given equations:

|z-3-5i| = 2r

arg(z-2) = 3π/4

Let's solve each equation separately:

  1. From the first equation, |z-3-5i| = 2r, we can rewrite it as:
  • √((x-3)² + (y-5)²) = 2r
  • (x-3)² + (y-5)² = 4r²
From the second equation, arg(z-2) = 3π/4, we can rewrite it as:
  • arg((x-2) + yi) = 3π/4
  • (y-2)/(x-2) = tan(3π/4)
  • Since tan(3π/4) = -1, we have (y-2)/(x-2) = -1
  • y-2 = -x+2
  • y = -x+4
Substitute y = -x+4 into the first equation:
  • (x-3)² + (-x+4-5)² = 4r²
  • x² - 6x + 9 + (x-1)² = 4r²
  • 2x² - 8x + 10 = 4r²
  • x² - 4x + 5 = 2r²
Since r is a real constant, 2r² is also a real number. Therefore, x² - 4x + 5 must be non-negative:
  • x² - 4x + 5 ≥ 0
  • (x-2)² + 1 ≥ 0
  • This inequality holds for all real values of x.

Hence, the exact range of values for the real constant r is (-∞, +∞).

User Stokes
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