BITSAT2024MathematicsMatricesActual
If A and B are symmetric matrices of same order such that A B+B A=X and A B-B A=Y , then (X Y)^ T =
Options
- AX Y
- BX^ Y^
- C-YX
- D-Y^ X^
Correct answer
C. -YX
Step-by-step solution
Since X Y=(A B+B A)(A B-B A)=( AB ) AB +( BA )( AB )-( AB )( BA )-( BA )( BA ) Now (X Y)^ T =(( AB ) ( AB ))^ T +( BA AB )^ T -( AB BA )^ T array r =( AB )^ T ( AB )^ T +( AB )^ T ( BA )^ T -( BA )^ T ( AB )^ T -( BA )^ T ( BA )^ T array = (B^ A^ ) (B^ A^ )+ (B^ A^ ) (A^ B^ )- ( A ^ B ^ ) ( B ^ A ^ )- ( A ^ B ^ ) ( A ^ B ^ ) Since, A & B are symmetric matrix. =( BA )( BA )+( BA )( AB )-( AB )( BA )-( AB )( AB )=( BA - AB )( BA + AB )=- YX