Question

Tìm x biết:

2x-1/3 = 27/2x-1

Answer 1

 \(\frac{2x-1}{3}=\frac{27}{2x-1}\)

\(\Rightarrow\left(2x-1\right)\left(2x-1\right)=27\cdot3\)

\(\Rightarrow\left(2x-1\right)^2=81\)

\(\Rightarrow\left(2x-1\right)^2=\left(\pm9\right)^2\)

\(\Rightarrow\orbr{\begin{cases}2x-1=9\\2x-1=-9\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}2x=10\\2x=-8\end{cases}}\)

\(\Rightarrow\orbr{\begin{cases}x=5\\x=-4\end{cases}}\)

ko bt đề đúng ý bn chưa ?

Answer 2

\(\frac{2x-1}{3}=\frac{27}{2x-1}\)

\(\Leftrightarrow\left(2x-1\right)^2=27.3=81\)

\(\Leftrightarrow\orbr{\begin{cases}2x-1=9\\2x-1=-9\end{cases}\Leftrightarrow\orbr{\begin{cases}2x=10\\2x=-8\end{cases}\Leftrightarrow}\orbr{\begin{cases}x=5\\x=-4\end{cases}}}\)

Answer 3

Mơn nhiều ạ...