ISI2017-MMA-20

Question

The number of ordered pairs $(X, Y)$, where $X$ and $Y$ are $n \times n$ real, matrices such that $XY-YX=I$ is

• A. $0$
• B. $1$
• C. $n$
• D. infinite

Comments

Taking both side trace. Then you get 0=1 , So no such matrix X, Y exists