a=matrix([[1,2,3,4],[3,4,5,6],[6,7,8,9],[3,4,5,6]])
X=det(a)
if ( X==1/2 ):
    print "valid"
    Y=det(2*a)
    print Y
    Z=det(-a)
    print Z
    C=inv(a)
    print C
    D=det(C)
    print D
    B=det(a**2)
    print B
else :
    print "not valied"

*<M.Pavan kumar>, <student>, <Prakasam engineering College> *<T.Raghavendra>, <student>, <Prakasam engineering College> *<B.Raghavendra>, <student>, <Prakasam engineering College> *<Y.Siva kumar Reddy>, <student>, <Prakasam engineering College>\ *<J.lakshmi narayana>, <student>, <Prakasam engineering College>