Let m and N be two 3x3 matrices such that MN=NM. Further if `M!=N^2` and `M^2=N^4` then which of the following are correct.
A. determinant of `(M^(2)+MN^(2))` is 0.
B. there is a `3 times 3` non-zero matrix U such that `(M^(2)+MN^(2))U` is the zero matrix.
C. determinant of `(M^(2)+MN^(2)) ge 1`
D. for a `3 times 3` matrix U, if `(M^(2)+MN^(2))U` equals the zero matrix then U is the zero matrix.