In this video I demonstrate how to prove that an identity element of a set G under a binary operation must be unique. These notes are based on Group Lessons, Pages 45-46, Further Pure Mathematics 2, Pearson. You can purchase this book via my Amazon affiliate link below. The proceeds will help support this channel. https://www.amazon.co.uk/shop/mathematics.proofs/list/1U280XC5SGSQU?ref_=aip_sf_list_spv_ofs_mixed_d This video was created by: https://www.twitter.com/tiago_hands For more mathematics content, check out: https://www.threads.net/@mathematics.proofs https://www.instagram.com/mathematics.proofs Thanks for watching this video and make sure you have subscribed if you want to see more videos like this! ... https://www.youtube.com/watch?v=zQjwQJcDnPY

This is a rotating Penrose Triangle Model which shows us the nature of one of the most popular optical illusions. It was created by Tom Ruen {https://en.wikipedia.org/wiki/User:Tomruen}. Animation details (attribution): Tomruen [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)] The Penrose Triangle is also known as the Penrose Tribar or Impossible Tribar. It is an optical illusion which can be depicted using an isometric grid. Isometric grids are commonly used for perspective drawings. The Penrose Triangle features prominently in the works of M. C. Escher and it's usually said that it was first created by the Swedish artist Oscar Reutersvärd in 1934. Source: https://en.wikipedia.org/wiki/Penrose_triangle Video description by Tiago Hands: https://www.instagram.com/tiago_hands/ *This video has not been monetised. ... https://www.youtube.com/watch?v=2fcbjOKVfoY