matematika



Logarithm(log, lg, ln)

If b = ac <=> c = logab
a, b, c
are real numbers and b > 0, a > 0, a ≠ 1
a
is called "base" of the logarithm.
Example: 23 = 8 => log28 = 3
the base is 2.

There are standrart notation of the logarithm if the base is 10 or e.

log10b = lg b
logeb = ln b

Graphs of logarithmic functions

Graphs of logarithmic functions

It shows that when x = 1, log = 0; when x -> 0 => log -> -∞; when x -> ∞ log -> ∞

Logarithm(log) properties

logaa = 1
loga(b.c) = logab + logac
loga(b/c) = logab - logac
logabn = n.logab
logba = 1/logab
logbc = logac/logab
logab = logac <=> b = c

Logarithm calculator

Select a logarithm base:
log2 =

If you have any question go to our forum about logarithms.


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