Identify and sketch the region in the complex plane satisfying

In summary, to identify and sketch the region in the complex plane satisfying the given inequality, it is recommended to rewrite the absolute value as the distance from z to a point, and then rationalize the denominator. Substituting z=x+yi into the inequality will result in a circle or ellipse, and the area outside this graph is the solution.
  • #1
complexnumber
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Homework Statement



Identify and sketch the region in the complex plane satisfying

[tex]
| \frac{2 z - 1}{z + i} | \geq 1
[/tex]

Homework Equations





The Attempt at a Solution

 
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  • #2
Geometrically, |z- a| is the distance from z to a as points in the complex plane so I recommend you try to rewrite the given absolute value in that way. It might help to "rationalize the denominator", multiplying both numerator and denominator by z- i.
 
  • #3
Let z=x+yi. Now simplify your inequality by: |2z-1| greater than or equal to |z+i|.(multiply out |z+i|). sub z=x+yi into this inequality. You will find that it gives a circle (if not its an ellipse, i may have made a quick error in attempting to answer this). The area outside this graph is your answer.
 

Related to Identify and sketch the region in the complex plane satisfying

1. What is the complex plane?

The complex plane is a geometric representation of the complex numbers, where the horizontal axis represents the real numbers and the vertical axis represents the imaginary numbers.

2. How do you identify a region in the complex plane?

To identify a region in the complex plane, you need to determine the points that satisfy a given condition or set of conditions. This can be done by graphing the complex numbers on the plane or by using equations to determine the points.

3. What is the process for sketching a region in the complex plane?

The process for sketching a region in the complex plane involves identifying the points that satisfy the given condition, plotting them on the plane, and connecting them to form a boundary. The region is then shaded in to indicate all the points within the boundary.

4. Can you give an example of a region in the complex plane?

One example of a region in the complex plane is the unit circle, which is the set of all complex numbers with a magnitude of 1. This can be represented by the equation |z| = 1, and the region can be sketched by plotting all points with a distance of 1 from the origin on the plane.

5. How can identifying and sketching regions in the complex plane be useful?

Identifying and sketching regions in the complex plane can be useful in many mathematical and scientific applications. It can help in solving equations and inequalities involving complex numbers, understanding the behavior of complex functions, and visualizing complex data in a two-dimensional space.

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