How to Determine Logarithm Value with Table

Logarithms that have 10 principal numbers are called ordinary. One way to determine the ordinary logarim value of a number is to use the help of logarithmic dafar. In the logarithmic list, only the mantise (decimal number of logarima retrieval results) is created so that the index number or the characteristic (integer of the logarithmic picking result) must be determined first.

1. Finding Logarithmic Results from Numbers Between 1 and 10

Since log 1 = 0 and log 10 = 1 then the 10 based logarithms of the numbers between 1 and 10 will lie between 0 and 1. So the index or its characteristic 0. Suppose log 2.345 has the index / characteristic 0. The numbers behind the comma are mantise can be obtained from the list of logarithms where the line 234 column 5 obtained number 3701. Notice the gamber logarithm table below:

So log 2,345 = 0.3701

2. Looking for Logarithmic Results of Numbers More Than 10

Log 10 = 1 and log 100 = 2, then the 10 based logarithms of the numbers between 10 and 100 will lie between 1 and 2. So the index or its characteristics 1.

Log 100 = 2 and log 1000 = 3, the base logarithm 10 of the numbers between 100 and 1000 will lie between 2 and 3. So the index or its characteristics 2 and so on.

Example:
Determine the logarithm value of log 19.69!

Answer:
The index of 19.69 is 1, its mantise is obtained from the list of rows 196 column 9 and there is a number 2942. Thus, log 19.69 is 1.2942.

3. Finding Logarithmic Results of Numbers Less than 1

Characteristics from 0.1 to 1 are -1
Characteristics of 0.01 to 0.1 are -2
Characteristics from 0.001 to 0.01 are -3, and so on

Example:
Please determine the logarithm value of log 0.9272!

Answer:
The index of 0.9272 is -1, its mantise is obtained from the list on line 927 column 2 and there are 9672 numbers. Thus, log 0.927 = 0.9672 - 1 = -0.0328

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