Before you tackle this problem see
Root Tracker.
In this problem you must first observe the path of the roots of the
quadratic equations
as you change
and keep
fixed.
You can change the equation
by moving the point
in the red frame. You can see how the graph of
changes in the blue frame. The Argand Diagram in the green frame shows the
roots of the quadratic equation. Look for two roots in the Argand diagram
and watch them move as
you change the driving point
in the red frame, and in doing so
change the quadratic equation and its roots.
What do you notice
about the paths that these roots follow when you change
and keep
fixed? Make a conjecture about the curves on which the complex roots lie.