Easy · Linear Algebra & Optimization · Numerical · ~4 min · #111

Determinant of a Random Symmetric Matrix

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The three distinct entries $a$ , $b$ , $c$ of the symmetric matrix $\begin{pmatrix} a & b \\ b & c \end{pmatrix}$ are drawn independently and uniformly from $[-60, 60]$ . What is the expected determinant?

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Concepts

Linearity of expectationVariance of a uniform

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