Question 2.7.18: (a) How many entries of A can be chosen independently, if A ...

Introduction to linear Algebra [EXP-672]

(a) How many entries of A can be chosen independently, if $A = {A}^{T}$ is 5 by 5?
(b) How do L and D (still 5 by 5) give the same number of choices in $LD{L}^{T}$ ?
(c) How many entries can be chosen if A is skew-symmetric? ( ${A}^{T} = -A$ ).

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