### Beautiful Books

This is an (ever-growing and ever-changing) list of books, useful for school and college mathematics students. If you are working …Read More

**Ashani DasguptaApril 12, 2015**

### I.S.I. Entrance Interview Problems

a and b are two numbers having the same no. of digits and same sum of digits (=28). Can one …Read More

**Ashani DasguptaJune 10, 2014**

### Math and Basic Science in India after school

We observe a renewed interest in basic science and mathematics in India after decades of engineering mania. This is a …Read More

**Ashani DasguptaJanuary 23, 2014**

### Initiating a child into the world of Mathematical Science

“How do I involve my son in challenging mathematics? He gets good marks in school tests but I think he …Read More

**Ashani DasguptaNovember 21, 2013**

### What is RMO and how to prepare for it

What is RMO RMO or Regional Math Olympiad is the first round of mathematics contest (in India) leading to the …Read More

**Ashani DasguptaNovember 14, 2013**

### A familiar Functional Equation

Cauchy’s functional equations are very simple. The most familiar one has a simple formula: f(x + y) = f(x) + …Read More

**Ashani DasguptaFebruary 16, 2018**

### Cauchy’s Functional Equation’s Application – INMO 2018 Problem 6

An Application of Cauchy’s Functional Equation Cauchy’s functional equation is a description of a function. $$ f(x + y) = …Read More

**Ashani DasguptaFebruary 5, 2018**

### Jensen’s Inequality (NBHM 2017 problem 5.2)

Question: Let \(n\in\mathbb{N}\), \(n\ge 2\). Let \(x_1,x_2,…,x_n\in(0,\pi)\). Set \(x=\frac{x_1+x_2+…+x_n}{n}\). Which of the following are true? A) \(\prod_{k=1}^{n} sinx_k \ge sin^nx …Read More

**Aritra BhattacharyaFebruary 1, 2018**

### INMO 2017

In the given figure, \(ABCD\) is a square sheet of paper. It is folded along \(E F\) such that \(A\) …Read More

**Sayoni ChakrabortyJanuary 30, 2018**

### INMO 2016

Let \(ABC\) be triangle in which \(AB=AC\). Suppose the orthocentre of the triangle lies on the incircle. Find the ratio …Read More

**Sayoni ChakrabortyJanuary 29, 2018**

### Contraction of a function – advanced Cheenta seminar

It is almost like deflating a balloon. But the effect is exponential. Today (29th January 2018, Monday), we have a …Read More

**Ashani DasguptaJanuary 29, 2018**

### INMO 2018

Let ABC be a non-equilateral triangle with integer sides. Let D and E be respectively the mid-points BC and C …Read More

**Sayoni ChakrabortyJanuary 28, 2018**

### Graphing the exponential (TOMATO Objective 699)

Graphing an exponential function can be tricky. We are familiar with the graph of \( e^x \). But what if …Read More

**Ashani DasguptaJanuary 26, 2018**

### Introducing Math Circle

In 2018, we are introducing Math Circle memberships. The members have exclusive access to: Weekly live and online Doubt Clearing …Read More

**Ashani DasguptaJanuary 23, 2018**