<PRE><B>Question 340228</B>
3(2i+3)(1+3i) =

NOTE: i^2 = -1

(6i + 9)(3i + 1) =

18i^2 + 6i + 27i + 9 =

18(-1) + 33i + 9 =

-18 + 33i + 9 =

-9 + 33i

Did you follow?

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