Question

se log y 81=2 e log2 8=x, então o valor de log3 (xy/27) é?

Answer 1

$log_{y}(81) = 2⇔ {y}^{2} = 81 \\ y = \sqrt{81} = 9$

$log_{3}( \frac{xy}{27} ) = log_{3}( \frac{3.9}{27} ) \\ = log_{3}(1) = 0$

$x = log_{2}(8) \\ x = 3$

Alternativa a