Tap the blue circles to see an explanation.
$$ \begin{aligned}(x^2+2x+2)(x+3)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}x^3+3x^2+2x^2+6x+2x+6 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}x^3+5x^2+8x+6\end{aligned} $$ | |
① | Multiply each term of $ \left( \color{blue}{x^2+2x+2}\right) $ by each term in $ \left( x+3\right) $. $$ \left( \color{blue}{x^2+2x+2}\right) \cdot \left( x+3\right) = x^3+3x^2+2x^2+6x+2x+6 $$ |
② | Combine like terms: $$ x^3+ \color{blue}{3x^2} + \color{blue}{2x^2} + \color{red}{6x} + \color{red}{2x} +6 = x^3+ \color{blue}{5x^2} + \color{red}{8x} +6 $$ |