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`[[2,3,-1,-1],[1,-1,-2,-4],[3,1,3,-2],[6,3,0,-7]]` Find rank of this matrix. |
Answer» Given matrix is, `[[2,3,-1,-1],[1,-1,-2,-4],[3,1,3,-2],[6,3,0,-7]]` Applying `R_4=>R_4-R_1-R_2-R_3` `=[[2,3,-1,-1],[1,-1,-2,-4],[3,1,3,-2],[0,0,0,0]]` As complete `R_4` is `0`, so rank can not be `4`. Now, we will take matrix, `[[2,3,-1],[1,-1,-2],[3,1,3]]` Determinant of the above matrix, `D = [2(-1)-3(9)-1(4)] = -33` As, `D !=0`, so we have a minor of `3 xx 3`. So, rank of the given matrix is `3.` |
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