Pengertian
Logaritma adalah invers dari perpangkatan atau eksponen sehingga antara eksponen dan logaritma mempunyai hubungan.
Rumus
\[log \ a \cdot b = log \ a + log \ b\]
\[^alog \ a = 1\]
\[log\frac{a}{b} = log \ a – log \ b = -log \frac{b}{a}\]
\[^alog \ 1 = 0\]
\[^alog \ b \cdot ^blog \ c = ^a log \ c\]
\[log \ a^n = n \ log \ a\]
\[a^n \ log \ b = ^alog \ b\frac{1}{n} = \frac{1}{n} ^alog \ b\]
\[a^n log \ b^k = \frac{k}{n} ^alog \ b\]
\[a^alog \ b = b^n\]
\[^alog \ b = \frac{log \ b}{log \ a} = \frac{1}{^blog \ a}\]
Contoh
\[^3 log \ 81 + ^2 log \ 32 – ^2 log \ 16\]
\[^3 log \ 3^4 + ^2 log 2^5 – ^2 log \ 2^4\]
\[4+5+4 = 13\]