`a,(x-3)^2+(x-3)=0`
`⇔(x-3)(x-3+1)=0`
`⇔(x-3)(x-2)=0`
⇔\(\left[ \begin{array}{l}x-3=0\\x-2=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=3\\x=2\end{array} \right.\)
Vậy x=3;x=2
`b,2x(x-2)-(2x-x)^2=0`
`⇔2x(x-2)+x(x-2)=0`
`⇔(x-2)(2x+x)=0`
`⇔2x.(x-2)=0`
⇔\(\left[ \begin{array}{l}x=0\\x=2\end{array} \right.\)
Vậy x=0;x=2
`c,x^2+36=12x`
`⇔x^2-12x+36=0`
`⇔(x-6)^2=0`
`⇔x=6`
Vậy x=6
`d,1/(16x^2)-x+4=0`
`⇔(1/(4x)-2)^2=0`
`⇔1/(4x)-2=0`
`⇔1/(4x)=2`
`⇔4x=1/2`
`⇔x=1/8`
Vậy x=1/8
`e,-x^3-7x+3x^2+21=0`
`⇔-x(x^2+7)+3(x^2+7)=0`
`⇔(x^7+7)(3-x)=0`
⇔\(\left[ \begin{array}{l}x²+7=0\\3-x=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x²=-7(loại)\\x=3\end{array} \right.\)
Vậy x=3
