a ) \(x^3-6x^2+12x-8=0\)
\(\Leftrightarrow x^3-3.x^2.2+3.x.2^2-2^3=0\)
\(\Leftrightarrow\left(x-2\right)^3=0\)
\(\Leftrightarrow\left(x-2\right)=0\)
\(\Leftrightarrow x=2\)
b ) \(x^3+9x^2+27x+27=0\)
\(\Leftrightarrow x^3+3.x^2.3+3.x.3^2+3^3=0\)
\(\Leftrightarrow\left(x-3\right)^3=0\)
\(\Leftrightarrow\left(x-3\right)=0\)
\(\Leftrightarrow x=3\)
a) x3 - 6x2 + 12x - 8 = 0
( x - 2 ) 3 = 0
x - 2 = 0
x = 2
b) x3 + 9x2 + 27x + 27 = 0
( x + 3 )3 = 0
x + 3 = 0
x = -3
