Question

(5x-1)⁶=729

tìm x

Answer 1

\(\left(5x-1\right)^6=729\)

\(\Rightarrow\left(5x-1\right)^6=3^6\)

\(\Rightarrow\left[{}\begin{matrix}5x-1=3\\5x-1=-3\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}5x=4\\5x=-2\end{matrix}\right.\)

\(\Rightarrow\left[{}\begin{matrix}x=\dfrac{4}{5}\\x=-\dfrac{2}{5}\end{matrix}\right.\)

Answer 2

=>(5x-1)^6=3^6

=>5x-1=3 hoặc 5x-1=-3

=>x=4/5 hoặc x=-2/5