Question 866711
{{{(3+10i)(4-9i)}}}



{{{3(4-9i)+10i(4-9i)}}}



{{{3(4)+3(-9i)+10i(4)+10i(-9i)}}}



{{{12-27i+40i-90i^2}}}



{{{12-27i+40i-90(-1)}}}



{{{12-27i+40i+90}}}



{{{102+13i}}}



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So, {{{(3+10i)(4-9i)=102+13i}}}