Question

calcule: ( dado o log2=0,3 e log3 = 0,48

a) log(3)81 =
b) log(12)1 =
c) log5 =
d) log6 =
e) log(a)a =

Answer 1

$a) \ log_381=x \Rightarrow 3^x=81 \Rightarrow 3^x=3^4 \Rightarrow x=4\\ \\ b) \ log_{12}1=x \Rightarrow 12^x=1 \Rightarrow x=0\\ \\ c) \ log5=log\frac{10}{2}=log10-log2=1-0,3=0,7\\ \\ d) \ log6=log(2*3)=log2+log3=0,3+0,48=0,78\\ \\ e) \ log_aa=x \Rightarrow a^x=a \Rightarrow x=1$