Mathematics

Rarely has a book so perfectly matched its title. The Gentle Man Who Taught Infinity by Sheshagiri KM Rao is one such and what a gentle read it was! Written as a tribute to the mathematics teacher who influenced his life, Sheshagiri Rao has managed to show us with his account just how far reaching a teacher’s influence can be and how this teacher did it, not commandingly or overtly or even intentionally but with his sheer love for the subject he taught and his innate respect for the students he taught.

In this article, we study the following problem. Three circles of equal radius r are centred at the vertices of an equilateral triangle ABC with side 2a. Here we assume that r > a. Find the area of the three-sided region DEF enclosed by all three circles, in terms of r and a.

W e are introduced to the concept of an even number and an odd number in primary school or even earlier. Any natural number divisible by 2 is even; if it is not, it is odd. The definition is extended to integers once we learn the arithmetic of negative whole numbers. Then we make simple observations such as: the sum of two even numbers is even, as is the sum of two odd numbers, and sum of an even number and an odd number is odd.

Here is an alternative solution to the following problem which was studied in the November 2016 issue of AtRiA:

Two sides of a triangle have lengths 6 and 10, and the radius of the circumcircle of the triangle is 12. Find the length of the third side.

The topic of cellular automata has many interesting and wide ranging applications to real life problems emerging from areas such as image processing, cryptography, neural networks, developing electronic devices and modelling biological systems. In fact cellular automata can be a powerful tool for modelling many kinds of systems.