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Simplify the given expression below:(1 + 2i) ⋅ (5 − 3i) (2 points) a2 − 15i b3 + 2i c5 − 6i d11 + 7i

User Marcel Kalveram
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1 Answer

17 votes
17 votes

Simplification of Algebraic Expression.


\begin{gathered} (1+2i)(5-3i) \\ \text{First, we clear the brackets. } \\ 1(5-3i)\text{ +2i(5 - 3i)} \\ \text{Multiplying through the brackets, we get} \\ 5\text{ -}3i+10i-6(-1) \\ \text{Note: i}^2=\text{ -1} \\ 5\text{ -3i + 10i +6} \\ C\text{ollecting like terms, we get} \\ 5\text{ + 6 -3i + 10i} \\ 11\text{ +7i} \end{gathered}

Thus, the correct answer is 11 +7i ( option D )

User Yevgen
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