most recent 30 from http://mathoverflow.net 2013-06-19T16:20:03Z http://mathoverflow.net/feeds/question/85522 http://www.creativecommons.org/licenses/by-nc/2.5/rdf http://mathoverflow.net/questions/85522/proof-of-the-neuman-lemma unknown (google) 2012-01-12T20:23:02Z 2012-01-12T20:23:02Z

<p>Prove that if <em>||A|| &lt; 1</em>, then <em>I-A</em> is invertible. Here, <em>||.||</em> is a matrix norm induced by a vector norm.</p> <p>This lemma is referred to as Neuman lemma.</p> <p>Any ideas on how to go ahead with this?</p> <p>Thanks.</p>