Question

me ajudem pfvrr T-T........​

Answer 1

Propriedade:

$(a^b)^c=a^{b.c}$

Vamos primeiro colocar 729 na base 3. Deste modo, com as bases iguais, podemos nos preocupar somente com os expoentes.

$(3^x)^{x+1}=729\\\\3^{x(x+1)}=3^6\\\\x(x+1)=6\\\\x^2+x-6=0\\\\\\x'+x''=\frac{-b}{a}=\frac{-1}{1}=-1\\\\x'.x''=\frac{c}{a}=\frac{-6}{1}=-6\\\\\\x=-3\:ou\:x=2$