Question

Considere log 2=0,3, Log 3=0,5 e log 5=0,7 determine o valor de: A) Log 15 B) Log 30 C) Log 45 D) Log 3,2

Answer 1

a) $log15 = log3*5 = log3+log5 = 0,5+0,7 = 1,2$
b) $log30 = log2*15 = log2+log15 = 0,3+1,2 = 1,5$
c) $log45 = log3*15 = log3+log15 = 0,5+1,2 = 1,7$
d) 

$log3,2 = log \frac{32}{10} = log32 - log10 \\ log2^5 - log10 = 5*log2-log10 = 5*0,3-1 = 1,5-1 = 0,5$