Question

3x-27x³=0

Answer 1

`3x-27x^3=0`

`<=>3x(1-9x^2)=0`

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

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

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

Answer 2

=>3x(1-9x²)=0

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

hay \(x\in\left\{0;\dfrac{1}{3};-\dfrac{1}{3}\right\}\)