Question

Dados log 2 = 0,3, log 3 = 0,48 e log 10 = 1 o valor de log 0,0006 é:a) 3,22 b) −4 c) −0,78 d) −4,78 e) −3,22

Answer 1

$\textrm{Algumas propriedades dos logaritmos:}\\\\ \mathrm{\log{a.b}=\log{a}+\log{b}\ \ \big\|\ \ \log{\bigg(\dfrac{a}{b}\bigg)}=\log{a}-\log{b}}\\\\ \mathrm{\log{0,0006}=\log{6.10^{-4}}=\log{2.3.10^{-4}}=}\\ \mathrm{=\log{2}+\log{3}+\log{10^{-4}}=0,3+0,48+(-4)=}\\ \mathrm{=0,78-4=-3,22}\\\\ \boxed{\mathbf{\log{0,0006}=-3,22}}\ \to\ \mathrm{Alt.\ E}$