Question

Tìm x :

a, \(3^x=9^{-6}.27^{-5}81^8\)

Answer 1

\(3^x=9^{-6}.27^{-5}.81^8\)

\(3^x=\left(3^2\right)^{-6}.\left(3^3\right)^{-5}.\left(3^4\right)^8\)

\(3^x=3^{2.\left(-6\right)}.3^{3.\left(-5\right)}.3^{4.8}\)

\(3^x=3^{-12}.3^{-15}.3^{32}\)

\(3^x=3^{\left(-12\right)+\left(-15\right)+32}\)

\(3^x=3^5\)

\(\Rightarrow x=5\)

Answer 2

\(3^x=9^{-6}.27^{-5}.81^8\)

\(3^x=3^{-12}.3^{-15}.3^{32}=3^5\)

\(x=5\left(dox\ne\pm1;0\right)\)

Vậy...