\Ans{Characteristic Equation: If A is a square matrix of order n with 
	elements $a_{ij}$, we can find a column matrix X and a constant 
	$\leftthreetimes$ such that AX=$\leftthreetimes$X or 
	AX-$\leftthreetimes$IX=0.
	On expansion, it gives an $n_{th}$ degree equation in 
	$\leftthreetimes$, called the characteristics equation of the matrix A. 
	Its roots $\leftthreetimes_i$ (i=1,2,...n) are called the eigen values. 
	And corresponding to each eigen value will have a non-zero solution 
	$$X=[x_1, x_2,
	x_3,.....x_n]'$$ 
	which is known as the eigen vector.}
