Thread: HELP needed!!! proof of invertible matrices

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any help or light on this question would be hugely appreciated!!

thank you

please read the forum rules concerning answering questions that count towards your grade.

i reply to this thread because i guess i know the answer.. i just wanna be updated with the progress...
@kaya2345- the solution shouldn't be difficult when you start working from the actual no. of entries in an nxn matrix...