Tìm x:
a)3x(x-2)-x+2=0
b)4x(x-3)-2x+6=0
c)2x^3+4x=0
d)(x-2)^2-(x-3)(x+3)=6
e)4(x-3)^6-(2x-1)(2x+1)=10
f)x^2+5x+6=0
g)x^3-9x^2+20x=0
Tìm x:
a)3x(x-2)-x+2=0
b)4x(x-3)-2x+6=0
c)2x^3+4x=0
d)(x-2)^2-(x-3)(x+3)=6
e)4(x-3)^6-(2x-1)(2x+1)=10
f)x^2+5x+6=0
g)x^3-9x^2+20x=0
$a) 3x(x-2)-x+2=0$
⇔$3x(x-2)-(x-2)=0$
⇔$(x-2)(3x-1)=0$
⇔\(\left[ \begin{array}{l}x-2=0\\3x-1=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=2\\x=\frac{1}{3}\end{array} \right.\)
$b)4x(x-3)-2x+6=0$
⇔$4x(x-3)-2(x-3)=0$
⇔$(x-3)(4x-2)=0$
⇔\(\left[ \begin{array}{l}x-3=0\\4x-2=0\end{array} \right.\)
⇔\(\left[ \begin{array}{l}x=3\\x=\frac{1}{2}\end{array} \right.\)
$c) 2x^{3}-4x=0$
⇔$2x(x^{2}-4)=0$
⇔$2x(x-2)(x+2)=0$
⇔$x=0$ $hoặc$ \(\left[ \begin{array}{l}x-2=0\\x+2=0\end{array} \right.\)
⇔$x=0$ $hoặc$ \(\left[ \begin{array}{l}x=2\\x=-2\end{array} \right.\)
$d)(x-2)^2-(x-3)(x+3)=9$
⇔$(x-2)^2-x^2+9=9$
⇔$(x-2)^2-x^2=0$
⇔\frac{