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QUESTION

If $z=2-j$ and $w=-1+3j$ find the real and imaginary parts of
$zw$.

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ANSWER

$zw=(2-j)(-1+3j)=-2+6j+j-3j^2=-2+7j-3(-1)$ i.e. $zw=1+7j.$
Therefore the real part is 1 and the imaginary part is 7.




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