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Question 4.E.3.8: Without doing any computation, determine whether the followi......

Without doing any computation, determine whether the following matrix is singular or nonsingular:

A = \begin{pmatrix}n& 1& 1& · · ·& 1\\1 &n& 1& · · ·& 1\\1 &1& n& · · ·& 1\\ \vdots&\vdots&\vdots&\ddots&\vdots\\1 &1& 1& · · ·& n\end{pmatrix}_{n×n}.

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A is nonsingular because it is diagonally dominant.

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