Question

ind such that .
Answer:

Answer 1

\(\Leftrightarrow3^{-m}=27.81=3^3.3^4=3^7\)

\(\Leftrightarrow-m=7\Rightarrow m=-7\)

Vậy \(m=-7\)

Answer 2

\(\frac{3^{-m}}{81}=27\)

\(\Leftrightarrow\left(3^{-m}\right)=27.81\)

\(\Leftrightarrow3^{-m}=3^7\)

\(\Leftrightarrow-m=-7\)

\(\Rightarrow m=7\)

Vậy m= 7