`<=> x^2(x-3) - 6x(x-3) + 9(x-3) = 0`
`<=> (x^2 - 2 . 3x + 3^2)(x-3) = 0`
`<=> (x-3)^3 = 0`
`<=> x - 3 = 0`
`<=> x = 3`
`x^3-9x^2+27x-27=0`
`<=>x^3-3.x^2 .3+3.x.3^2-3^3=0`
`<=>(x-3)^3=0`
`<=>x-3=0`
`<=>x=3`
\(x^3-9x^2+27x-27=0\\ \Leftrightarrow\left(x-3\right)^3=0\\ \Leftrightarrow x-3=0\\ \Leftrightarrow x=3\)
`d)x^3 -9x^2 +27x-27=0`
`=> x^3 - 3.x^2 .3 +3. x.3^2 -3^3 =0`
`=>(x-3)^3 =0`
`=>x-3=0`
`=>x=3`
d)x3−9x2+27x−27=0d)x3-9x2+27x-27=0
⇒x3−3.x2.3+3.x.32−33=0⇒x3-3.x2.3+3.x.32-33=0
⇒(x−3)3=0⇒(x-3)3=0
⇒x−3=0⇒x-3=0
⇒x=3
giúp em câu 6,9,10 câu này khó em k làm dc![[Waanjai] Rùa](https://hoc24.vn/images/avt/avt29452625_256by256.jpg)
