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puhsyers
Jan23-12, 11:24 PM
Hi everyone,

This not a homework question. I'm reviewing some linear algebra and I found this on a worksheet. I just need a hint on how to approach this problem.

Let β=\{ v_1,v_2,...,v_n\} be a basis for R^n . Let M be the matrix whose columns are the basis vectors in β. Do the columns of M^2 form a basis?

I've played around with some examples and it seems to be true. I know that M has full rank and hence invertible, therefore, M^2 is also invertible and has full rank. But this only means the columns of M^2 spans the vector space. How do I show the columns are also linearly independent?

homeomorphic
Jan24-12, 12:44 AM
If the columns are linearly dependent, then it doesn't have full rank. My definition of rank is the dimension of the space spanned by the columns.