The long tales of a tail/less ape

February 18, 2017 Saturday

Bedtime Story

Understanding Logarithm

You know that:

5 X 5 X 5 = 125

Exponentially we can write it as 5³ = 125

So 125 can be expressed in terms of 5 using the cubic function.

Mathematicians love to do the opposite operations or rather the inverse operations of every possible thing they get their hands into.

Now they wondered how can 5 be expressed in terms of 125?

Voila, they announced the root function.

So 5 = 3√125 (cube root of 125).

This was still not enough for them.

Now they wanted to express that 3 in terms of 5 and 75.

How to go about it.

Herein they invented the logarithmic function which is the inverse operation to exponentiation.

So if 125 = 5³

Then log₅125 = 3 or 3 = log₅125

Isn’t this a beautiful way of expressing 3 in terms of 5 and 125?

In words these figures are summed up this way:

The logarithm of 125 to the base 5 is 3.

So in general, if x = b^y then

Log_b(x) = y

Logarithm of x to the base b is y.

Now let us address the domain issue of logarithmic function.

Unlike the squaring function of last night, logarithm function does not work for negative numbers.

Nor does it work for zero.

It is only applicable to the positive numbers.

Thus we say that the domain of the logarithmic function is the natural numbers or the positive integers..

Having understood what a function is, we can now proceed to computable functions.

So what are computable functions?

I think I should not overburden your precious brain cells and hence I have decided to take the computable functions up in the nights to come.

Stay tuned to the voice of an average story storytelling chimpanzee or login at http://panarrans.blogspot.in/

Good night mon ami and my fellow cousin ape.

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Another great educator and a teacher that I am aware of is Professor Subhashish Chattopadhyay in Bangalore, India.

While I narrate stories, Professor Subhashish an electronic engineer and a former professor at BARC, does and teaches real mathematics and physics.

He started the participation of Indian students at the International Physics Olympiad.

Do visit him here:

All his books can be downloaded for free through this link:

For edutainment and English education of your children, I recommend this large collection of Halloween Songs for Kids:

Saturday, February 18, 2017