(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

If A is a rectangular n*m matrix (n>m) , and all the columns of A is orthonormal.

I know that A'*A=I, where A' stands for its transpose.

but A*A'<>I as I've learned from wiki. but is there an estimate for [tex]\|A \cdot A'\| [/tex]?

2. Relevant equations

http://en.wikipedia.org/wiki/Orthogonal_matrix

in the rectangular matrix section.

3. The attempt at a solution

I have tried to write A in component form to find any hints. but i failed to solve the problem. but when i test A*A' , i always find that norm(A*A')=1, could you help me to explain it? Thank you in advance.

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# Homework Help: Orthonormal matrix

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