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If A=[[1 ,0 ,1],[0 ,1, 2],[ 0, 0, 4]], t...

If `A=[[1 ,0 ,1],[0 ,1, 2],[ 0, 0, 4]]`, then show that `|3A| = 27|A|`

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`A = [[1,0,1],[0,1,2],[0,0,4]]`

`:. 3A = [[3,0,3],[0,3,6],[0,0,12]]`
`|A| = 1(4-0)-0(0-0)+1(0-0) = 4`
`|3A| = 3(36-0)-0(0-0)+3(0-0) = 108`
We are given,
`27|A| = 4**27 = 108`
Thus, `|3A| = 27|A|`
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