Logarithms - multiplication
Mathematicians found an easier way.
Instead of multiplying numbers, they added powers (indices/exponents) and adding is a lot easier.
From our knowledge of indices.
`a^m\timesa^n = a^(m+n)`
or `10^2\times10^2 = 10^4`
`(10\times10)\times (10\times10) = (10\times10\times10\times10)`
Here is the example again
`69.31\times 57.43`
This is the same as `10^(1.8408)\times 10^(1.7591)` (see next page for explanation)
Add the indices
This equals `10^(3.5999)`
And `10^(3.5999) = 10^3\times 10^(0.5999)`
`= 1000\times 3.980`
`= 3980`
(see next sections for explanation)
![](/images/user/base/Maths/Logarithms/Reference%20Tables/reference-log-table-1.4df6ee6.jpg)
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