# Need help : Rank of Determinant

### Need help : Rank of Determinant

Please , I need help for the attached question . Thanks

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Mahmoud Ibrahim

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### Re: Need help : Rank of Determinant

If rank of A is 2 , then the determinant of A must be equal to 0 ( det A = 0 ) Det A = 2.0.(-1) + 4.3.k+1.1.2 - 2.0.3 - 1.(-1).k-2.4.1=12k+2 - 8 +k =13k - 6
$detA=0\Leftrightarrow k = \frac{6}{13}$

nathi123

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### Re: Need help : Rank of Determinant

Thanks very much.

Mahmoud Ibrahim

Posts: 7
Joined: Mon May 21, 2018 4:42 am
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