If show that A2 – 2A + 3I2 = 0.
Given:
I2 is an identity matrix of size 2, so
To show that
Now, we will find the matrix for A2, we get
[as cij = ai1b1j + ai2b2j + … + ainbnj]
Now, we will find the matrix for 2A, we get
Now,
So,
Substitute corresponding values from eqn(i), (ii) and (iii), we get
[as rij = aij + bij + cij]
Therefore,
Hence proved