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If A=[(n,0 ,0),( 0,n,0),( 0, 0,n)] and B...

If `A=[(n,0 ,0),( 0,n,0),( 0, 0,n)]` and `B=[(a_1,a_2,a_3),(b_1,b_2,b_3),(c_1,c_2,c_3)]` , then `A B` is equal to (A) `B` (B) `n B` (C) `B^n` (D) `A+B`

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Given:`A=[(n,0 ,0),( 0,n,0),( 0, 0,n)]` and `B=[(a_1,a_2,a_3),(b_1,b_2,b_3),(c_1,c_2,c_3)]`
Then
`AB=[(n,0 ,0),( 0,n,0),( 0, 0,n)][(a_1,a_2,a_3),(b_1,b_2,b_3),(c_1,c_2,c_3)]`
`AB=[(na_1,na_2,na_3),(nb_1,nb_2,nb_3),(nc_1,nc_2,nc_3)]`
`AB=nB`
Hence correct option is (b).
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