

InterviewSolution
Saved Bookmarks
1. |
If A is a square matric of order 5 and `2A^(-1)=A^(T)`, then the remainder when `|"adj. (adj. (adj. A))"|` is divided by 7 isA. 2B. 3C. 4D. 5 |
Answer» Correct Answer - A We have, `2A^(-1)=A^(T)` `implies |2A^(-1)|=|A^(T)|` `implies 2^(5) 1/(|A|)=|A|` `implies |A|^(2)=2^(5)` `:. |"adj. (adj. (adj. A))"|=|A|^(4^(3))=(|A|^(2))^(32)=2^(160)` `2^(160)/7=(2(2^(3))^(53))/7=(2(7+1)^(53))/7= m+2/7`, where m is integer Thus, required remainder is 2. |
|