Foundation and University publication

AtRiA, November 2019 focuses on journeys -some are enjoyable, some tiresome, some endless. A mathematician’s journey is full of unexpected delight, simply because of unexpected detours, sudden discoveries and interesting alternatives. Have fun as you travel with us. Read all about the young Yatris and their journey of discovery in Features. This section also describes more abstract journeys from the Regular Pentagon to the Icosahedron and the Dodecahedron (Part 2) and from the familiar 2 and 3 dimensions to n dimensions in Extension of the Pythagorean Theorem. In ClassRoom, Simple Cryptography and Triangles with Integer Sides are articles sparked off by previous articles in AtRiA . An Unusual Proof of the Centroid Theorem, Modified Pascal Triangle and Orthocentre of a Triangle may motivate you to write similarly! You will find ideas in our regular columns – How to Prove It, Low Flow High Ceiling and TechSpace which features the simulation of a dice game this time. Our issue is short of 100% without the PullOut, enjoy the learning trajectory on Percentages, defined and illustrated with plenty of examples in this issue. How Craig Barton Wishes he’d Taught Maths is an excellent review by Sir Timothy William Gowers, reprinted from his Weblog. If not yet subscribed for hard copy send in your brief profile and postal address to AtRightAngles@apu.edu.in and do share your feedback at AtRiA.editor@apu.edu.in

November, 2019

A Mathematical Pilgrimage: Ramanujan Yatra

Vinay Nair

Extensions of the Theorem of Pythagoras

Laxman N. Katkar

From Regular Pentagons to the Icosahedron and Dodecahedron via the Golden Ratio – II

Shashidhar Jagadeeshan

Brahmagupta’s Theorem

M Narasimha Murthy

Simple Cryptography

Megharaj Bhatt

Generalising the Divisibility Tests of 9 and 11

A. Ramachandran

An Unusual Proof of the Centroid Theorem

Rajatadri Venkatasubban

A Modified Pascal Triangle

Anand Prakash

Explorations on Triangles with Integer Sides

Shreyan Jha

TearOut Isometric Sketches and More

Swati Sircar

Low Floor High Ceiling Tasks In-cyclic Quads

Swati Sircar

How to Prove it

Shailesh Shirali

Orthocentre of a Triangle and its Distance from any Point in the Plane

Avipsha Nandi

The Game of Craps

Jonaki B Ghosh

Middle School Problems on Averages

A Ramachandran

Problems for the Senior School

PRITHWIJIT DE & SHAILESH SHIRALI

A Challenging Geometric Construction Problem

Jaleel Radhu

How Craig Barton Wishes he’d Taught Maths

Sir William Timothy Gowers

Percentages

Padmapriya Shirali