Question

Considerando log 2=0,301 ; log 3= 0,477;log5= 0,699 e log 7= 0,845 , determine : $(\frac{7}{5} )$

Answer 1

$log\frac{7}{5}=log7-log5=0,845-0,699=0,146$

Answer 2

Lembre-se que, $\text{log}~\frac{a}{b}=\text{log}~a-\text{log}~b$.

Assim, $\text{log}~\frac{7}{5}=\text{log}~7-\text{log}~5$.

Pelo enunciado, $\text{log}~7=0,845$ e $\text{log}~5=0,699$.

Deste modo, $\text{log}~\frac{7}{5}=0,845-0,699~~\huge\Rightarrow~~\huge\boxed{\text{log}~\frac{7}{5}=0,146}$.