Question 1177869
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It is about the MODULUS of a complex number.


    |(1+i)*(2+i)| = |(2 + 2i + i + i^2| = |(2-1) + 3i| = |1+3i| = {{{sqrt(1^2 + 3^2)}}} = {{{sqrt(1+9)}}} = {{{sqrt(10)}}}.    <U>ANSWER</U>
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Solved, answered, explained and completed.