Question

va rog e urgeeent
doresc rezolvare completa

Answer 1

 

$\displaystyle\\\frac{x}{x+3}=\frac{3^{2014}-3^{2013}-3^{2012}}{3^{2014}+3^{2013}+3^{2012}}\\\\\frac{x}{x+3}=\frac{3^{2012+2}-3^{2012+1}-3^{2012}}{3^{2012+2}+3^{2012+1}+3^{2012}}\\\\\frac{x}{x+3}=\frac{3^{2012}\times3^2-3^{2012}\times3^1-3^{2012}}{3^{2012}\times3^2+3^{2012}\times3^1+3^{2012}}\\\\\frac{x}{x+3}=\frac{3^{2012}\Big(3^2-3^1-1\Big)}{3^{2012}\Big(3^2+3^1+1\Big)}\\\\\frac{x}{x+3}=\frac{5}{13}\\\\13x=5(x+3)\\13x=5x+15\\\\13x-5x=15\\8x=15\\\\\boxed{x=\frac{15}{8}}$