Question

Dados log 2 = 0,30 ,log 3 = 0,48 , log 5 = 0,70 e log 7 = 0,85 calcule :
A) log 15
B) log 42
C) log 1,5

Answer 1

$a)log 15=log3.5=log3+log5=0,48+0,70=1,18$
$b)log42=log7.6=log7+log6=log7+log2.3=log7+log2+log3$
$0,85+0,48+0,30=1,63$
$c)log1,5=log \frac{15}{10}=log15-log10=1,18-1=0,18$

Answer 2

A)0,70X3=2,1
B)0,48X2+0,85=1,81
C)0,48-0,30=0,12