Tap the blue circles to see an explanation.
| $$ \begin{aligned}(1+i)\cdot(2+3i)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}2+3i+2i+3i^2 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}3i^2+5i+2\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{1+i}\right) $ by each term in $ \left( 2+3i\right) $. $$ \left( \color{blue}{1+i}\right) \cdot \left( 2+3i\right) = 2+3i+2i+3i^2 $$ |
| ② | Combine like terms: $$ 2+ \color{blue}{3i} + \color{blue}{2i} +3i^2 = 3i^2+ \color{blue}{5i} +2 $$ |