Principles of Mathematics

Use of Logarithm

When do we use Logarithm operation?     Let’s see an example.

Solve 2^X = 4.    The solution is simple   2^X = 2²  ===> X = 2 (answer).

How about solving   2^X = 5 ?

In this case, 5 cannot be expressed as a base of 2.     So how?

Step 1:  Perform logarithm operation on BOTH sides.     log 2^X = log 5

Step 2: Using Power Law of Logarithm, it becomes x log 2 = log 5

Step 3:  x = log 5 / log 2 = 0.699 / 0.301 = 2.322 (answer)    Is it simple?

This is one application of logarithm to solve a problem.

Article submitted by: Lim Ee Hai
Article Source:   http://www.limeehai.com