Question

Tìm x : 

( x - 6 ) ^ 3 = ( x - 6 ) ^ 2

Answer 1

(x - 6)³ = (x - 6)²

Th1:

x - 6 = 1

x = 1 + 6

x = 7

Th2:

x - 6 = 0

x = 6

Vậy x = 7 hoặc x = 6

Answer 2

\(\left(x-6\right)^3=\left(x-6\right)^2\)

\(\Leftrightarrow\left(x-6\right)^3-\left(x-6\right)^2=0\)

\(\Leftrightarrow\left(x-6\right)^2.\left[\left(x-6\right)-1\right]=0\)

\(\Leftrightarrow\left(x-6\right)^2.\left(x-7\right)=0\)

\(\Leftrightarrow\left[\begin{array}{nghiempt}x-6=0\\x-7=0\end{array}\right.\)

\(\Leftrightarrow\left[\begin{array}{nghiempt}x=6\\x=7\end{array}\right.\)

Vậy \(x=6;7\)