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#chain-rule
2 articles
01
2026-08-25
·
Calculus & Optimization
·
★ MEMBER
·
11 min read
Matrix Calculus from Scratch — Derive the Backward Pass Yourself
Where does the transpose in ∂L/∂W = XᵀG actually come from? Matrix calculus is not a formula sheet to memorize — it is one move: rotate dX to the right inside a trace. From denominator layout and shape-checking to the gradients of a linear layer and softmax + cross-entropy, ending with a double-precision gradient check.
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.