## Determinant of Matrix whose Diagonal Entries are 6 and 2 Elsewhere

## Problem 380

Find the determinant of the following matrix

\[A=\begin{bmatrix}

6 & 2 & 2 & 2 &2 \\

2 & 6 & 2 & 2 & 2 \\

2 & 2 & 6 & 2 & 2 \\

2 & 2 & 2 & 6 & 2 \\

2 & 2 & 2 & 2 & 6

\end{bmatrix}.\]

(*Harvard University, Linear Algebra Exam Problem*)

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