a=var('a')
b=var('b')
c=var('c')
d=var('d')
A=matrix([[a,a,a,a],[b,b,b,b],[c,c,c,c],[d,d,d,d]])
print det(A)
I=matrix([[1,0,0,0],[0,1,0,0],[0,0,1,0],[0,0,0,1]])
print det(I+A)

Strang-4.2 32-U (last edited 2010-12-18 10:27:50 by shwetaradha)