Question

log 5 na base 3 × log 81 na base 25

Answer 1

$log_{3}5 . log_{25}81 \\ \\ log_{3}5 . \frac{log_{3}3^{4}}{log_{3}5^{2}} \\ \\ \frac{log_{3}5}{log_{3}5^{2}}}.log_{3}3^{4} \\ \\ \frac{log_{3}5}{2.log_{3}5}.log_{3}3^{4} \\ \\ \frac{1}{2} .4 = 2$

Espero ter ajudado.