New posts in Orthogonality

Spectral norm of projected matrix

Where am I going wrong in calculating the projection of a vector onto a subspace?

Find a vector NOT perpendicular to a given set of vectors

Bounded operator on Hilbert space is orthogonal projection

Visualize the proof of $\mathcal{H} = M \oplus M^{\perp}$, where $\mathcal{H}$ Hilbert space, $M$ closed subspace

Why are $(\,f_1,...,f_n)$ linearly independent if $\|\,f_k-e_k\|_2<\dfrac{1}{\sqrt n}$, where $(e_k)$ is an orthonormal basis?

What does $A^{-1}=A^T$ have to do with “orthogonality”?

A characterization of 'orthogonal' matrices

Let $A$ be a real $4\times4$ matrix such that $A^2+A+I = 0$. Can $A$ be orthogonal?

Characterization of Parseval Frame