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If the matrix `A` and `B` are of `3xx3` and `(I-AB)` is invertible, then which of the following statement is/are correct ?A. `I-BA` is not invertibleB. `I-BA` is invertibleC. `I-BA` has for its inverse `I+B(I-AB)^(-1)A`D. `I-BA` has for its inverse `I+A(I-BA)^(-1)B` |
Answer» Correct Answer - B::C `(b,c)` Let `(I-AB)^(-1)=P` `impliesP(I-AB)=I` `impliesP-PAB=I` `impliesPB^(-1)-PA=B^(-1)` `impliesBPB^(-1)-BPA=I` `impliesBPB^(-1)=I+BPA` Now `BPB^(-1)=B(I-AB)^(-1)B^(-1)` `=B(B(I-AB))^(-1)` `=(B^(-1))^(-1)(B(I-AB))^(-1)` `=(B(I-AB)B^(-1))^(-1)` `=((B-BAB)B^(-1))^(-1)` `=(I-BA)^(-1)` |
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