Question

(7/9)^1/3-x = (9/7)^x Ajudem pfvr...

Answer 1

Olá Annacarol,

use a propriedade da exponenciação..

$\large\boxed{\left(\dfrac{a}{b}\right)^n~\to~\left( \dfrac{b}{a}\right)^{-n}}$

$\left( \dfrac{7}{9}\right)^{ \tfrac{1}{3}-x }=\left( \dfrac{9}{7}\right)^x\\\\ \left( \dfrac{7}{9}\right)^{ \tfrac{1}{3}-x }=\left( \dfrac{7}{9}\right)^{-x}\\\\ \left( \dfrac{\not7}{\not9}\right)^{ \tfrac{1}{3}-x }=\left( \dfrac{\not7}{\not9}\right)^{-x}\\\\ \dfrac{1}{3}-x=-x\\\\ \dfrac{1}{3}=-x+x\\\\ \dfrac{1}{3}=0~~(impossivel)\\\\\\ \Large\boxed{\boxed{S=\{\emptyset\}}}$

Tenha ótimos estudos ;D