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Section7Unitary Matrices (NM, 18 Sep)

Definition7.1

A matrix \(Q \in \Cmm\) is unitary if its columns form an orthogonal, orthonormal set.

It follows that \(Q^{-1} =Q^\star\text{.}\)

Subsection7.1Exercise(s)

Exercise7.2(Exercise 2.1 of [2])

Show that if a matrix is both triangular and unitary, then it is diagonal.

Hint