Bn Đời về cơ bản là buồn... cười!!! nhìn sai đề ở ý a .

a) \(\left(\dfrac{1}{3}-\dfrac{1}{2}\right)^{x-1}=\dfrac{1}{36}\)

\(\Leftrightarrow\left(-\dfrac{1}{6}\right)^{x-1}=\dfrac{1}{36}\)

\(\Leftrightarrow\left(-\dfrac{1}{6}\right)^{x-1}=\dfrac{1}{6}^2\)

\(\Leftrightarrow x-1=2\Rightarrow x=3\)

b) \(\dfrac{25}{5^x}=\dfrac{1}{125}\Leftrightarrow\dfrac{25}{5^x}=\dfrac{25}{3125}\Leftrightarrow\dfrac{25}{5^x}=\dfrac{25}{5^5}\Rightarrow x=5\)

a) \(\left(\dfrac{1}{3}-\dfrac{1}{2}\right)^{x-1}=\dfrac{1}{36}\) \(\Leftrightarrow\left(\dfrac{-1}{6}\right)^{x-1}=\dfrac{1}{36}\)

\(\Leftrightarrow\left(\dfrac{-1}{6}\right)^{x-1}=\left(\dfrac{1}{6}\right)^2\)

\(\Leftrightarrow x-1=2\Rightarrow x=3\)

b) \(\dfrac{25}{5^x}=\dfrac{1}{125}\Leftrightarrow\dfrac{25}{5^x}=\dfrac{25}{3125}\Leftrightarrow\dfrac{25}{5^x}=\dfrac{25}{5^5}\Rightarrow x=5\)