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If the matrix A B is zero, then It is no...

If the matrix `A B` is zero, then It is not necessary that either `A=O` or, `B=O` (b) `A=O` or `B=O` (c) `A=O` and `B=0` (d) all the above statements are wrong

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Given : the matrix `A B` is zero
Then take `A=[(0,0),(4,0)]` and `B=[(0,0),(1,0)]`
As `AB=[(0,0),(4,0)][(0,0),(1,0)]`
`AB=[(0,0),(0,0)]`
As we see here none of A and B are nul matrices.
Hence, if `AB` is zero it is not necessary that either `A=O` or `B=O`.
Therefore correct option is (a)
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