regions-in-argand-diagrams

Inequalities & regions in Argand diagrams

How do I sketch inequalities such as or  on an Argand diagram?

• The inequality  is satisfied by all complex numbers, , with a real part less than 2

  • On an Argand diagram, this would be the region to the left of the vertical line 

  • The vertical line itself, , should be drawn dotted to show that points on this line are not permitted due to the strict inequality (<)

• In general, dotted lines are used with strict inequalities ( < or > ) and solid lines are used with inequalities that can be equal ( ≤ or ≥ )

• Here is how to represent the following inequalities as regions on an Argand diagram…

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