Tap the blue circles to see an explanation.
| $$ \begin{aligned}x(x-1)(x-2)((x-1)^2-3(x-1)+1)& \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle1}{\textcircled {1}} } }}}x(x-1)(x-2)(x^2-2x+1-3(x-1)+1) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle2}{\textcircled {2}} } }}}(x^2-x)(x-2)(x^2-2x+1-(3x-3)+1) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle3}{\textcircled {3}} } }}}(x^3-2x^2-x^2+2x)(x^2-2x+1-(3x-3)+1) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle4}{\textcircled {4}} } }}}(x^3-3x^2+2x)(x^2-2x+1-(3x-3)+1) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle5}{\textcircled {5}} } }}}(x^3-3x^2+2x)(x^2-2x+1-3x+3+1) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle6}{\textcircled {6}} } }}}(x^3-3x^2+2x)(x^2-5x+5) \xlongequal{ } \\[1 em] & \xlongequal{ \color{blue}{ \text{\normalsize{ \htmlClass{explanationCircle explanationCircle7}{\textcircled {7}} \htmlClass{explanationCircle explanationCircle8}{\textcircled {8}} } }}}x^5-8x^4+22x^3-25x^2+10x\end{aligned} $$ | |
| ① | Find $ \left(x-1\right)^2 $ using formula. $$ (A - B)^2 = \color{blue}{A^2} - 2 \cdot A \cdot B + \color{red}{B^2} $$where $ A = \color{blue}{ x } $ and $ B = \color{red}{ 1 }$. $$ \begin{aligned}\left(x-1\right)^2 = \color{blue}{x^2} -2 \cdot x \cdot 1 + \color{red}{1^2} = x^2-2x+1\end{aligned} $$ |
| ② | Multiply $ \color{blue}{x} $ by $ \left( x-1\right) $ $$ \color{blue}{x} \cdot \left( x-1\right) = x^2-x $$Multiply $ \color{blue}{3} $ by $ \left( x-1\right) $ $$ \color{blue}{3} \cdot \left( x-1\right) = 3x-3 $$ |
| ③ | Multiply each term of $ \left( \color{blue}{x^2-x}\right) $ by each term in $ \left( x-2\right) $. $$ \left( \color{blue}{x^2-x}\right) \cdot \left( x-2\right) = x^3-2x^2-x^2+2x $$ |
| ④ | Combine like terms: $$ x^3 \color{blue}{-2x^2} \color{blue}{-x^2} +2x = x^3 \color{blue}{-3x^2} +2x $$ |
| ⑤ | Remove the parentheses by changing the sign of each term within them. $$ - \left( 3x-3 \right) = -3x+3 $$ |
| ⑥ | Combine like terms: $$ x^2 \color{blue}{-2x} + \color{red}{1} \color{blue}{-3x} + \color{green}{3} + \color{green}{1} = x^2 \color{blue}{-5x} + \color{green}{5} $$ |
| ⑦ | Multiply each term of $ \left( \color{blue}{x^3-3x^2+2x}\right) $ by each term in $ \left( x^2-5x+5\right) $. $$ \left( \color{blue}{x^3-3x^2+2x}\right) \cdot \left( x^2-5x+5\right) = x^5-5x^4+5x^3-3x^4+15x^3-15x^2+2x^3-10x^2+10x $$ |
| ⑧ | Combine like terms: $$ x^5 \color{blue}{-5x^4} + \color{red}{5x^3} \color{blue}{-3x^4} + \color{green}{15x^3} \color{orange}{-15x^2} + \color{green}{2x^3} \color{orange}{-10x^2} +10x = \\ = x^5 \color{blue}{-8x^4} + \color{green}{22x^3} \color{orange}{-25x^2} +10x $$ |