A PHASE relation familiar to students of applied mathematics exists between a simple harmonic oscillation and its derivative. Similar relations exist between exponential functions and their ...

Let A → Ar be the map that takes a positive definite matrix to its rth power, and let DAr be the Fréchet derivative of this map. It is known that ∥DAr∥ = ∥rAr−1∥ if r ≤ 1 or if r ≥ 2, and also that ...