Showing posts with label Mathematics. Show all posts
Showing posts with label Mathematics. Show all posts

Saturday, April 4, 2009

The Funny Side of Mathematics

During my interview for IIM Indore, which coincidentally was my first experience of  an "IIM Interview", I yelled a few times that I am good at mathematics and I should be asked questions on that. I also mentioned I would like to teach mathematics etc etc, lets leave the details.

The learned professor, who was supposed to ask the tech( acads maths etc) questions suddenly asked, " Can you prove 1=2?".

For a moment, I was like what? Then I told him that it is wrong thing, and all the proofs that you get in forwarded emails and fun sites are wrong and flawed.

He said, yes it is flawed, can you tell me the flaw?

I somehow ws not able to recollect this simple thing there, but I did it as soon as I was outside the room, interview blues I guess.

So the readers of this blog do not have such a problem, let me explain some ways to prove 1=2.

Method 1

x^2= x+x+x+x+x... ( x times)

differentiate both sides wrt x

then we get

2x=1+1+1+1+.. (x times)

2x=x

=>1=2

everything looks good, isn't it ? But it  is flawed. I leave it to the reader to figure out the flaw? if not, I will explain the flaw in one of teh comments. Kindly bear with me !

Method 2

1/4=1/4

(1/2)^2=(-1/2)^2

taking square root both sides

1/2=-1/2

add 3/2 both sides

2=1

This is much simpler and the flaw is also visible, i.e square roots are always positive .

Found it funny? Not yet?

One of my other friends was asked to tell when is pie day celebrated?

Innocent though he was, did not take a guess. You can always hazard a guess pie =3.14  so it has to be 14 march ( American calendar)

There is also a pie approximation day and yes you guessed it right, it is 22/7 that is 22 july ( english calendar).

Ramanujam's Number

A friend of mine, who as well proclaimed himself as math wiz in one of the IIM Interviews, was asked tell me about 1729?

And he was a wiz? Yes you guessed it right. He answered it well. 1729=10^3+9^3=1^3+12^3

It is the smallest number which can be written as the sum of two cubes in two different ways. It is a very famous number, so if you dare to proclaim maths as your hobby, you must know it.

Want to more? wikipedia, my friend! ( Indians must know about Ramanujam)

Thats all!

Cheers1