Linear Algebra Question: Matrix multiplied by a column of its inverse

DrexelDan
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X is a 10x10 matrix

what is X*[7th column of X's inverse]?

thanks for any help you can provide!
 
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I'm sure that I can just make a matrix up then find its inverse and multiply the original by the 7th column of the inverse but is there a general rule for doing this?
 
I also know that a matrix multiplied by its inverse is the identity matrix. would the resultant matrix of the problem above be: in one column [0 0 0 0 0 0 1 0 0 0]
 
DrexelDan said:
I also know that a matrix multiplied by its inverse is the identity matrix. would the resultant matrix of the problem above be: in one column [0 0 0 0 0 0 1 0 0 0]

You've got it.
 
Thanks!
 
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