Cauchy's functional equations are very simple. The most familiar one has a simple formula: f(x + y) = f(x) + f(y) But first, for the uninitiated, what is a functional equation after all? What is a functional equation? Usually, functions appear as formulae. For example ( f(x) = x^2 ) is a function. It takes […]
Lets look at Indian National Math Olympiad 2018's Problem 6 which can be solved as an application of Cauchy's Functional Equation.
This post contains problems from Indian National Mathematics Olympiad, INMO 2017. Try them and share your solution in the comments. INMO 2017, Problem 1 In the given figure, \(ABCD\) is a square sheet of paper. It is folded along \(E F\) such that \(A\) goes to a point \(A'\) different from Band \(C\), on the […]
This post contains problems from Indian National Mathematics Olympiad, INMO 2016. Try them and share your solution in the comments. INMO 2016, Problem 1 Let \(ABC\) be triangle in which \(AB=AC\). Suppose the orthocenter of the triangle lies on the incircle. Find the ratio \(AB/BC\). INMO 2016, Problem 2 For positive real numbers \(a, b, […]
It is almost like deflating a balloon. But the effect is exponential. Today (29th January 2018, Monday), we have a special concept building cum problem-solving session on Contraction of a function. When 10 PM I.S.T. (29th January 2018) Where: Online (link will be posted in Cheenta Commons, Open Slate skype group) […]
This post contains problems from Indian National Mathematics Olympiad, INMO 2018. Try them and share your solution in the comments. INMO 2018, Problem 1 Let ABC be a non-equilateral triangle with integer sides. Let D and E be respectively the mid-points BC and C A, let G be the centroid of triangle ABC. Suppose D, […]
The most beautiful equation in mathematics is: It is often attributed to Swiss Mathematician Leonhard Euler. Interestingly enough, this is nothing but a statement about rotation! 23 is a shorthand way of writing 2 × 2 × 2. But this is very very different from what means. Mathematicians use this trick over and over again. They overload notations. In fact is a […]
We have indicated the source of these problems. Do not look up solutions. It is fun to try it yourself or see others try them live! Let P be an interior point of triangle ABC and AP, BP, CP meet the sides BC, CA, AB in D, E, F respectively. Show that \( \frac{AP}{PD}=\frac{AF}{FB}+\frac{AE}{EC} \) […]
Sine of an angle, half chord and vertical projection Note that half chord corresponding to a half arc is same as the magnitude of vertical projection.
Watch the solution of an interesting problem on Triangles on a sphere and learn how to solve it. You may try the problem yourself and then watch the video. PROBLEM Suppose the earth is a perfect sphere. You are on its surface at point A. First, you walk 1 mile south, then 1 mile east […]