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