Question 549368: Déterminer la valeur de K pour que la matrice suivante sois inversible:
K 3 K
8 6 8
1 2 3
Thanks Found 2 solutions by stanbon, Alan3354:Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! Déterminer la valeur de K pour que la matrice suivante sois inversible:
K 3 K
8 6 8
1 2 3
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The determinant:
(K*6*3+8*2*K+1*8*3)-(k*6*1+8*2K+3*8*3) = 0
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18k+16k+24-(6k+16k+72) = 0
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(34k+24)-(22k+72) = 0
12k - 48 = 0
k = 4
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The matrix is singular if k = 4;
It is invertible if k is not 4.
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Cheers,
Stan H.
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