Definition:Log Tables/Historical Note

Historical Note on Log Tables

Before the advent of inexpensive electronic calculators, the use of log tables was a standard technique for multiplication of multi-digit numbers.

The technique consisted of:

$(1): \quad$ Use the log tables to find the logarithms of $x$ and $y$ to obtain $\log_{10} x$ and $\log_{10} y$.

$(2): \quad$ Add those logarithms to obtain $\log_{10} x y$.

$(3): \quad$ Use the log tables to find the antilogarithm of $\log_{10} x y$.

The result is $x y$.