Question

Qual o valor de x na equação exponencial 3^x=1/9 ?

Answer 1

3^x=1/9
3^x=(9/1)^-1
3^x=(3^2)^-1
3^x=3^-2
Logo:
x=-2

Answer 2

$3^{x}=\dfrac{1}{9}~~\Rightarrow~~ 3^{x}=\dfrac{1}{3^2}~~\Rightarrow~~3^{x}=3^{-2}~~\Rightarrow~~\boxed {x=-2}$