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#jacobian
2 articles
01
2026-08-27
·
Calculus & Optimization
·
★ MEMBER
·
11 min read
Jacobians and Hessians — Multivariable Calculus, Drawn
The Jacobian is a magnifying glass at a point; the Hessian is how sharply the ground curves there. From local linearization to what eigenvalues say about the terrain, why Newton's method is fast on paper but absent in practice, and how to get Hessian information in a billion dimensions without ever building the matrix.
02
2026-08-05
·
Calculus & Optimization
·
FREE
·
7 min read
Calculus for AI — The Gradient Is an Arrow Saying Which Way Is Better
No epsilon-delta limits, no integration by parts. Training is measuring a slope and stepping the other way. A derivative is a multiplier, a gradient is a list of slopes, the chain rule is multiplication — and Jacobians and Hessians only need to be recognised, not computed.