12.3: Reading Questions
What is a nonsingular matrix? Give an example of a \(2 \times 2\) nonsingular matrix. How do you know your example is nonsingular?
What is an isometry in \(\mathbb R^n\text{?}\) Can you give an example of an isometry in \(\mathbb R^2\text{?}\)
What is an orthonormal set of vectors?
What is the difference between the orthogonal group and the special orthogonal group?
What is a lattice?