Question

log27 x+ log3 x =4 qual a resposta ?

Answer 1

vamos lá...

$\log_{27}x+\log_3x=4$ 

mudar para a base 3

$\frac{\log_3x}{\log_327} +\log_3x=4 \\ \\\log_327=\log_33^3=3\log_33=3.(1)=3 \\ \\ \frac{\log_3x}{3} +\log_3x=4 \\ \\ mmc=3 \\ \\ \log_3x+3\log_3x=12 \\ \\ 4\log_3x=12 \\ \log_3x=12\div4 \\ \\ \log_3x=3 \\ \\ x=3^3 \\ \\ x=27$