Question
Answer
$$(-6+8i)\cdot(-3-5i)=-40i^2+6i+18$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}(-6+8i)\cdot(-3-5i)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}18+30i-24i-40i^2 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}-40i^2+6i+18\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{-6+8i}\right) $ by each term in $ \left( -3-5i\right) $. $$ \left( \color{blue}{-6+8i}\right) \cdot \left( -3-5i\right) = 18+30i-24i-40i^2 $$ |
| ② | Combine like terms: $$ 18+ \color{blue}{30i} \color{blue}{-24i} -40i^2 = -40i^2+ \color{blue}{6i} +18 $$ |
This page was created using
Complex Expression calculator