Inverse for Complex Multiplication/Examples/1+i

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Example of Inverse for Complex Multiplication

$\dfrac 1 {1 + i} = \dfrac {1 - i} 2$


Proof

\(\ds \dfrac 1 {1 + i}\) \(=\) \(\ds \dfrac {1 - i} {\paren {1 + i} \paren {1 - i} }\) multiplying top and bottom by $1 - i$
\(\ds \) \(=\) \(\ds \dfrac {1 - i} {1^2 + 1^2}\) simplifying
\(\ds \) \(=\) \(\ds \dfrac {1 - i} 2\) simplifying

$\blacksquare$