Ramanujan

摘要： Consider the following exercise, found in a generic linear algebra textbook.Let A be an n × n matrix. Prove that the following statements are equivalent:A is invertible.Ax = b has exactly one solution for every n × 1 matrix b.Ax = b is consistent for every n × 1 matrix b.Ax = 0 has on 阅读全文

摘要： Knights of the Round TableTime Limit: 7000MSMemory Limit: 65536KTotal Submissions: 8288Accepted: 2632DescriptionBeing a knight is a very attractive career: searching for the Holy Grail, saving damsels in distress, and drinking with the other knights are fun things to do. Therefore, it is not very su 阅读全文