Level:
Project ID:
2000017409
Accepted:
0
Clonable:
0
Easy:
0
Let
\[
A=\left (\array{
1& 2\cr
a & 1 \cr
} \right ) ,
\ B=\left (\array{
7& 4 \cr
6 & 7 \cr
} \right ),
\]
where \(a\) is a real number. For which \(a\) the equality \(A \cdot B = B \cdot A\) holds?
\( 3\)
\( -3\)
\( 3.5\)
\( -3.5\)
Fixed Answer:
None