Line 1: Line 1:
 
<h1> Inverse of a Matrix </h1>
 
<h1> Inverse of a Matrix </h1>
  
<p> An <i>n</i> x <i>n</i> matrix <i>A</i> is said to have an inverse provided there exists an <i>n</i> x <i>n</i> matrix <i>B</i> such that <i>AB</i> = <i>BA</i> = <i>I</i>.  We call <i>B</i> the inverse of <i>A</i> and denote it as <i>A</i><sup>-1</sup>.  In this case, A is also called nonsingular.  
+
<p> An <i>n</i> x <i>n</i> matrix <i>A</i> is said to have an inverse provided there exists an <i>n</i> x <i>n</i> matrix <i>B</i> such that <i>AB</i> = <i>BA</i> = <i>I</i><sub>n</sub>.  We call <i>B</i> the inverse of <i>A</i> and denote it as <i>A</i><sup>-1</sup>.  Thus, <i>A</i><i>A</i><sup>-1</sup> = <i>A</i><sup>-1</sup><i>A</i> = <i>I</i><sub>n</sub>.  In this case, A is also called nonsingular.  
  
  

Revision as of 07:43, 10 December 2012

Inverse of a Matrix

An n x n matrix A is said to have an inverse provided there exists an n x n matrix B such that AB = BA = In. We call B the inverse of A and denote it as A-1. Thus, AA-1 = A-1A = In. In this case, A is also called nonsingular.

Alumni Liaison

To all math majors: "Mathematics is a wonderfully rich subject."

Dr. Paul Garrett