Question
Answer
$$(x-9)(x^2+x+2)=x^3-8x^2-7x-18$$
Explanation
Tap the blue circles to see an explanation.
| $$ \begin{aligned}(x-9)(x^2+x+2)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}x^3+x^2+2x-9x^2-9x-18 \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}x^3-8x^2-7x-18\end{aligned} $$ | |
| ① | Multiply each term of $ \left( \color{blue}{x-9}\right) $ by each term in $ \left( x^2+x+2\right) $. $$ \left( \color{blue}{x-9}\right) \cdot \left( x^2+x+2\right) = x^3+x^2+2x-9x^2-9x-18 $$ |
| ② | Combine like terms: $$ x^3+ \color{blue}{x^2} + \color{red}{2x} \color{blue}{-9x^2} \color{red}{-9x} -18 = x^3 \color{blue}{-8x^2} \color{red}{-7x} -18 $$ |
This page was created using
Simplify polynomials calculator