NDA2012MathematicsMatricesActual
If the matrix AB is a zero matrix, then which one of the following is correct?
Options
- AA must be equal to zero matrix or B must be equal to zero matrix
- BA must be equal to zero matrix and B must be equal to zero matrix
- CIt is not necessary that either A is zero matrix or B is zero matrix
- DNone of the above
Correct answer
C. It is not necessary that either A is zero matrix or B is zero matrix
Step-by-step solution
If A= [ array ll 2 & 0 0 & 0 array ], B= [ array ll 0 & 0 2 & 0 array ] then, A B= [ array ll 0 & 0 0 & 0 array ] Here A 0, ~B 0 but AB =0 .