How (and why) to raise e to the power of a matrix | DE6
by Grant Sanderson · 3Blue1Brown
A 27-minute animated lecture, chapter 6 of 3Blue1Brown's differential equations series. It defines the matrix exponential through its Taylor series and shows why exp(Mt) solves linear systems x' = Mx, visualized as flow in state space. Best geometric intuition for the topic's central object, the matrix exponential, and its link to state-space flow.
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Wolfram MathWorld
MathWorld is an online mathematics encyclopedia from Wolfram Research offering detailed, browsable articles on topics across the math spectrum, including algebra, geometry, calculus, and number theory. Each entry includes definitions, theorems, formulas, diagrams, worked examples, and links to further reading.
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