Tap the blue circles to see an explanation.
| $$ \begin{aligned}(2x-1)(x+3)(x+1)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}(2x^2+6x-x-3)(x+1) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}(2x^2+5x-3)(x+1) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}2x^3+2x^2+5x^2+5x-3x-3 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle4}{\textcircled {4}} } }}}2x^3+7x^2+2x-3\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{2x-1}\right) $ by each term in $ \left( x+3\right) $. $$ \left( \color{blue}{2x-1}\right) \cdot \left( x+3\right) = 2x^2+6x-x-3 $$ |
| ② | Combine like terms: $$ 2x^2+ \color{blue}{6x} \color{blue}{-x} -3 = 2x^2+ \color{blue}{5x} -3 $$ |
| ③ | Multiply each term of $ \left( \color{blue}{2x^2+5x-3}\right) $ by each term in $ \left( x+1\right) $. $$ \left( \color{blue}{2x^2+5x-3}\right) \cdot \left( x+1\right) = 2x^3+2x^2+5x^2+5x-3x-3 $$ |
| ④ | Combine like terms: $$ 2x^3+ \color{blue}{2x^2} + \color{blue}{5x^2} + \color{red}{5x} \color{red}{-3x} -3 = 2x^3+ \color{blue}{7x^2} + \color{red}{2x} -3 $$ |