Find Formula for z in Complex Quadratic Equation

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Homework Statement



consider

[tex]a*z - b*conj(z) + c = 0[/tex]

where a,b,c are unknown complex constants.

find a formula for z in terms of a, b, c

answer should be in the form "z = ..." where the ... does not contain any z or conj(z)

Homework Equations



I multiply the whole equation by z

[tex]z*(a*z - b*conj(z) + c) = 0[/tex]

=

[tex]a*z^2 - b*z^2 + c*z) = 0[/tex]

=

[tex](a - b)*z^2 + c*z = 0[/tex]

using the quadratic formula

[tex]z = \frac {-c \frac {+}{-} \sqrt{c^2}}{2*(a-b)}[/tex]
is this correct?

thanks!

The Attempt at a Solution

 
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No, [itex]z\overline{z}=|z|^2\neq z^2[/itex] in general.

Instead, take the complex conjugate of both sides of your original equation. That will give you two equations and two unknowns ([itex]z[/itex] and [itex]\overline{z}[/itex]) which you should know how to solve.