Đáp án`+`Giải thích các bước giải:
` a. x^2 (x-4) - (x-4) = 0`
`-> (x-4)(x^2 - 1) = 0`
`-> (x-4)(x-1)(x+1)=0`
`->` \(\left[ \begin{array}{l}x-4=0 ; x-1=0\\x+1=0\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x=4;x=1\\x=-1\end{array} \right.\)
` b . x^3 - 2x^2 = -x`
`-> x^3 - 2x^2 + x = 0`
`-> x(x^2 - 2x + 1)=0`
`-> x(x - 1)^2 = 0`
`->` \(\left[ \begin{array}{l}x=0\\x-1=0\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x=0\\x=1\end{array} \right.\)
` c. 5x(x-1) - 2x+2=0`
`-> 5x(x-1) -2(x-1)=0`
`-> (x-1)(5x-2)=0`
`->` \(\left[ \begin{array}{l}x-1=0\\5x-2=0\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x=1\\x=2/5\end{array} \right.\)
` d. (5-x1)(x-3) + 3-x = 0`
`-> (5x-1)(x-3) + (3-x)=0`
`-> (5x-1)(x-3) - (x-3)=0`
`-> (x-3)[(5x-1)-1] = 0`
`-> (x-3)(5x-1-1)=0`
`-> (x-3)(5x-2)=0`
`->` \(\left[ \begin{array}{l}x-3=0\\5x-2=0\end{array} \right.\)
`->` \(\left[ \begin{array}{l}x=3\\x=2/5\end{array} \right.\)
