Logarithms

Logarithms

N= a x log a N=x \({\log _a}N = x\) is called the logarithmic form and \(N = {a^x}\) is the index or exponential form.



Note:
  1. The logarithm of a negative number is not defined.
  2. log in the calculator denotes \({\log _{10}}\) or common logarithm.
  3. \({\log _{10}}\) may be written as lg.
  4. If the base is other than 10, the base should be specified, e.g. \({\log _3}81\)