Complex Conjugate/Examples/conj z1 - conj z2

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Example of Complex Conjugates

Let $z_1 = 4 - 3 i$ and $z_2 = -1 + 2 i$.

Then:

$\overline {z_1} - \overline {z_2} = 5 + 5 i$


Proof 1

An illustration of the modulus of the difference of the complex conjugates of the complex numbers:

$z_1 = 4 - 3 i$
$z_2 = -1 + 2 i$

is given below:


Complex-Conjugate-z1-z2.png


$\blacksquare$


Proof 2

\(\ds \overline {z_1} - \overline {z_2}\) \(=\) \(\ds \paren {\overline {4 - 3 i} } - \paren {\overline {-1 + 2 i} }\) Definition of $z_1$ and $z_2$
\(\ds \) \(=\) \(\ds \paren {4 + 3 i} - \paren {-1 - 2 i}\) Definition of Complex Conjugate
\(\ds \) \(=\) \(\ds \paren {4 - \paren {-1} } + \paren {3 - \paren {-2} } i\) Definition of Complex Subtraction
\(\ds \) \(=\) \(\ds 5 + 5 i\)

$\blacksquare$