If A = x 4
.........y 7
(^^^^ that is a 2x2 matrix)
determine the values of x and y for which A^2=A.
No idea how to start this one.
i didnt think it was possible because
A^2 = x^2 16
..........y^2 49
A = x 4
......y 7
so how can A^2 ever equal A because no matter what the x and y values are, 4 and 7 will never equal 16 and 49?
Help please
Thank you