Question

Qual o conjunto solução de:


Log2ˣ - 9.log8ˣ = 4

Answer 1

vamos lá...

$\log_2x-9\log_8x=4 \\ \\ mudar~~\log_8x~~para~~base~~2 \\ \\ \log_2x- \frac{9\log_2x}{\log_28} =4 \\ \\ \log_2x- \frac{9\log_2x}{3} =4 \\ \\ mmc=3 \\ \\ 3\log_2x-9\log_2x=12 \\ \\-6\log_2x=12 \\ \\ \log_2x=12\div-6 \\ \\ \log_2x=-2 \\ \\ x=2^{-2} \\ \\ x= \frac{1}{2^2} = \frac{1}{4}$