How Do You Graph the Complex Inequality |z-1|<|z|?

In summary, a complex inequality is an equation or inequality involving one or more variables and real and/or imaginary numbers. To graph a complex inequality, it needs to be rewritten in the form of y = mx + b and plotted accordingly. The difference between a simple and complex inequality is the number of variables and the inclusion of imaginary numbers. A graphing calculator can be used to graph a complex inequality by inputting the equation and using appropriate settings. The solution to a complex inequality can be determined by the shaded region on the graph, with strict inequalities having the shaded region on one side of the line or curve.
  • #1
torquerotates
207
0

Homework Statement


Graph the inequality: |z-1|<|z| where z=x+iy {i is the imaginary number: (-1)^.5}


Homework Equations


for complex #'s z and w,
|w+z|<or=|w|+|z|
|z-w|>or=|z|-|w|


The Attempt at a Solution



|z|-|1|<or=|z-1|<|z| { if we consider 1 to be complex i.e 1=1+0i}
=>|z|-1<|z|
=>-1<0

I have no idea how to graph this last inequality. Isn't it just a true statement in general?
 
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  • #2
torquerotates said:

Homework Equations


for complex #'s z and w,
|w+z|<or=|w|+|z|
|z-w|>or=|z|-|w|

Huh? What do these inequalities (which are always true) have to do with the inequality in the question?

Instead, use [itex]z=x+iy[/itex] to calculate both [itex]|z|[/itex] and [itex]|z-1|[/itex] in terms of x and y and then substitute your results into the given inequality.
 
  • #3
Also, one can interpret |x- y|, geometrically, as the distance form x to y in the complex plane. That means that we can think of |z- 1| as the distance from z to 1+ 0i or from (x,y) to (1, 0) and |z| as the distance from z to 0+0i or from (x,y) to (0,0). Saying that |z-1|< |z| means the point (x,y) is closer to (1, 0) than to (0,0).
The line x= 0.5 (the complex numbers 0.5+ yi for any real number y) is the perpendicular bisector of the interval from (0,0) to (1,0). That line is the set of points z so that |z-1|= |z|. The points for which |z-1|< |z| is the set of points to the right of that line.
 

FAQ: How Do You Graph the Complex Inequality |z-1|<|z|?

What is a complex inequality?

A complex inequality is an equation or inequality with one or more variables that involve real and/or imaginary numbers. It can also involve multiple operations such as addition, subtraction, multiplication, and division.

How do you graph a complex inequality?

To graph a complex inequality, you first need to rewrite it in the form of y = mx + b, where y is the dependent variable, x is the independent variable, m is the slope, and b is the y-intercept. Then, plot the y-intercept on the y-axis and use the slope to determine additional points to plot on the graph. Finally, connect the points with a line or curve depending on the type of inequality (greater than or less than).

What is the difference between a simple inequality and a complex inequality?

A simple inequality involves one variable and real numbers, while a complex inequality involves one or more variables and can involve both real and imaginary numbers.

Can you use a graphing calculator to graph a complex inequality?

Yes, you can use a graphing calculator to graph a complex inequality. Input the equation into the calculator and use the appropriate settings to graph it. Some graphing calculators even have the option to shade the region representing the solution to the inequality.

How do you determine the solution to a complex inequality from its graph?

The solution to a complex inequality is represented by the shaded region on the graph. If the inequality is greater than or equal to, the shaded region will be above the line or curve. If the inequality is less than or equal to, the shaded region will be below the line or curve. If the inequality is strict (greater than or less than), the shaded region will be on one side of the line or curve, not including the line or curve itself.

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