Question

log o,64 com a base 1,25

Answer 1

$Log_{1,25}0,64 = x\\Log_{125/100}64/100 = x\\Log_{25/20}16/25 = x\\Log_{5/4}(4/5)^{2} = x\\Log_{5/4}(5/4)^{-2} = x\\\\x = -2$

Dúvidas só perguntar.