Can we find characteristic and minimal polynomial forming block....if so pls once tell

yes ,There is a way to find characteristic polynomial of A using characteristic polynomial of block diagonal matrix. *characteristic polynomial of A is just multiplication of charp...

this is very conceptual theory....I suggest you plz study step by step ... characteristics, then minimal polynomial ,then Jordan blocks....then you have no doubt about this theory....

there is no shortcut method to find ch. and min. polynomial , we have to find by finding det(A-xI)=0 .

see example

this is not Jordan form of matrix A....if Jordan form is given then we can find both ... minimal polynomial and characteristics equation...I explain you by a example