Answer
$$(-1+2i)\cdot(2+2i)=4i^2+2i-2$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}(-1+2i)\cdot(2+2i)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}-2-2i+4i+4i^2 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}4i^2+2i-2\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{-1+2i}\right) $ by each term in $ \left( 2+2i\right) $. $$ \left( \color{blue}{-1+2i}\right) \cdot \left( 2+2i\right) = -2-2i+4i+4i^2 $$ |
| ② | Combine like terms: $$ -2 \color{blue}{-2i} + \color{blue}{4i} +4i^2 = 4i^2+ \color{blue}{2i} -2 $$ |
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