Question

resolva a equaçao exponencial : 2^x+2+2^x-1=18

Answer 1

2ˣ⁺²  + 2ˣ⁻¹ = 18

(2ˣ * 2² ) + ( 2ˣ / 2¹ =  18

Fazendo  2ˣ  = y e substituindo acima
( y * 4 ) + ( y/2 ) = 18
4y/1 + y/2 = 18/1
mmc = 2
8y + y = 36
9y = 36
y = 36/9 = 4 ou 2² 

y = 2ˣ = 2²
x = 2 ****

PROVA
2²⁺²  + 2²⁻¹  = 18
2⁴ + 2¹ = 18
16 + 2 = 18
18 = 18 CONFERE