Question

tìm x 

3x^2(2x+1)-6x(1+2x)=0 

Answer 1

=>3x(2x+1)(x-2)=0

=>x=0; x=-1/2;x=2

Answer 2

`3x^2(2x+1)-6x(1+2x)=0`

`<=>3x(2x+1)(x-2)=0`

`<=>3x=0` hoặc `2x+1=0` hoặc `x-2=0`

`<=>x=0:3` hoặc `2x=-1` hoặc `x=0+2`

`<=>x=0` hoặc `x=-1/2` hoặc `x=2`

vậy `3x^2(2x+1)-6x(1+2x)=0 ` có `x=0;x=-1/2;x=2`

Answer 3

`3x^2(2x+1)-6x(1+2x)=0 `

`<=> (3x^2 -6x ) (2x+1) =0`

`<=> 3x(x-2)(2x+1) =0`

`<=> [(3x=0),(x-2=0),(2x=-1):}`

`<=> `\(\left[{}\begin{matrix}x=0\\x=2\\x=-\dfrac{1}{2}\end{matrix}\right.\)

Vậy `S={0;2;-1/2}`