Question

(3x - 1 )^10 = (3x - 1 ) ^20

Answer 1

Đề bài yêu cầu tìm gì thế?

Answer 2

\(\left(3x-1\right)^{10}=\left(3x-1\right)^{20}\)

\(\Rightarrow\left(3x-1\right)^{10}=\left(3x-1\right)^{20}=0\)

\(\Rightarrow\left(3x-1\right)^{10}.\left[\left(3x-1\right)^{10}-1\right]=0\)

\(\Rightarrow\orbr{\begin{cases}\left(3x-1\right)^{10}=0\\\left(3x-1\right)^{10}-1=0\end{cases}\Rightarrow\orbr{\begin{cases}3x-1=0\\3x-1=\pm0\end{cases}}}\)

\(\left(+\right)3x-1=0\Rightarrow x=\frac{1}{3}\)

\(\left(+\right)\orbr{\begin{cases}3x-1=1\\2x-1=-1\end{cases}\Rightarrow\orbr{\begin{cases}x=\frac{2}{3}\\x=0\end{cases}}}\)

\(\Rightarrow x\in\left\{\frac{1}{3};\frac{2}{3};0\right\}\)