||'''Book'''|| Linear Algebra ||
 ||'''Author'''|| Gilbert Strang ||
 ||'''Edition'''||  ||

/* code_begins */

{{{
A=matrix([[3,4+1*i],[4-1*i,6]])
a=A[0,0]
b=A[0,1]
c=A[1,1]
ac= a*c
b2= abs(b)**2
print ac
18
print b2
17
#ac>b2
#therefore A is positive definite
}}}

/* code_ends */

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