Subtraction Through Addition | Complimentary Addition | Easy Way Addition | Tricks In Addition
Channel: Magic Square Puzzles
Date: 2020-11-29

Can we do subtraction through addition?

It seems curious, isn't it? 

But yes. We can do subtraction through addition. This is also called the Complimentary addition.

In this method, we find the compliment number for every number and do the addition to actually perform the subtraction.

Where is this used?

This is used in computers. The computers can not do subtraction. They can do only addition.

We use the 2's complement to do addition, subtraction, etc.

I was introduced into this concept and I first came in contact with P.K. Srinivasan through his book on 'Addition through Subtraction'. Curious to know more about this I first went to his house then situated in Nanganallur one evening and spent about an hour or so discussing various things in general and Mathematics in particular.
He was such a nice soul and a teacher. His room was filled with books, books and more books. Though God had blessed him with a big family and a big house, he was living alone with his books. 
To navigate into his room is itself a very complicated job because you have to find a track amidst a huge pile of books.

Books about mathematics, Srinivasa Ramanujan, Euler etc.

His house had the Euler's formual written on it.
His gates contained the birthday magic squares. 
The name of his house was, if I remember it right 'Alarsri'. 'Sri' stands for Srinivasan, I believe. I don't remember his wife's name. 
His sons'' Govindarajan, Rangarajan et al are good friends of mine.
He never distinguished between any of us, outsiders and his own sons.
He was called a teacher's teacher by one IIT Professor.
He was the Director of Ramanujan Museum, situated in Royapuram, Chennai and he presented my Mother Late. Indira Narasinga Rao with an award for coming out with a 1000 x 1000 magic square.
A few years down the line I was also awarded at the Ramanjan Museum for my works in magic squares and coming out with a book titled Magic Square Puzzles.
My Magic Square Puzzles are being published daily in THE HINDU IN SCHOOL a sister publication from THE HINDU, which caters exclusively to the schools.
Had he been alive my magic square puzzles would have gone all over the world and helped students all over the world.
I miss you sir.
In a way, we are your torchbearers. We carry forward your tradition and your legacy.
I will always remember you sir.