Question

dado log2 = 0,30 e log3 = 0,47 determine o valor do logaritmo log15

Answer 1

$log_{10}(a) = log (a)$
$log_{x}(x) = 1$
$log_{x} (a*b) = log_{x}a + log_{x}b$
$log_{x}(a/b) = log_{x}a - log_{x}b$
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$log 15 = log(3*5)$
$log15 = log(3*10/2)$
$log15 = log3 + log10 - log2$
$log15 = 0,47 + 1 - 0,30$
$log15 = 1,17$