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QUESTION

If $z=1+j$ find the real and imaginary parts of $3z^*-z$.

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ANSWER


$z=1+j,\ z^*=1-j,\ 3z^*-z=3(1-j)-(1+j)=2-4j\\Re(3z^*-z)=2,\
Im(3z^*-z)=-4$



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