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2 votes
2 votes
Simplify (4+2i)(1+5i)

User Gary Murakami
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1 Answer

19 votes
19 votes

The simplyfied expression is: -6 + 22i

To multiply two complex numbers, we need to apply distributive propiertie with each term of each parentheses. In this case:


\mleft(4+2i\mright)\mleft(1+5i\mright)=4\cdot1+4\cdot5i+2i\cdot1+2i\cdot5i

Now we can solve:


4+20i+2i+(2\cdot5)i^2

i^2 is (-1). Then:


\begin{gathered} 4+22i+10(-1) \\ 4-10+22i \\ -6+22i \end{gathered}

-6+22i is the simplified expression

User Dayamoy
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