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