5.(3x - 2)² - 3³: 3² = 2
=> 5.(3x - 2)² - 3 = 2
=> 5.(3x - 2)² = 2+3
=> 5.(3x - 2)² = 5
=> (3x - 2)² = 5 : 5
=> (3x - 2)² = 1
=> 3x-2 = 1 = -1
=> \(\left[ \begin{array}{l}3x-2=1\\3x-2=-1\end{array} \right.\)
=> \(\left[ \begin{array}{l}x=1\\x=\frac{1}{3}\end{array} \right.\)
Vậy x=1 hoặc x=$\frac{1}{3}$