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COMPLETE INDEX

6 notes across 6 subjects, newest first.

Last note added 14 Sep 2026 · back to the overview

Real analysis

1 note · 14 Aug 2026Subject page
  1. A new proof classifying continuous non-constant solutions of f(x+y)f(x−y)=f(x)²−f(y)² using finite-dimensional translation spaces and Lie group projections.

Topology

1 note · 11 Aug 2026Subject page
  1. Continuity

    An equivalent characterization of continuity for functions on A ⊆ ℝ: the preimage of every open set is open in the subspace topology.

Geometry

1 note · 11 Aug 2026Subject page
  1. Deriving the exterior derivative of a 1-form as a 2-form in Euclidean space.

Lie theory

1 note · 11 Aug 2026Subject page
  1. Cover Linear

    Solving the Cauchy-type functional equation f(xy)=f(x)+f(y) under monotonicity assumptions, with extensions to weaker regularity conditions such as continuity and measurability.

Mathematical modeling

1 note · 1 Sep 2026Subject page
  1. Balancing departure time and walking speed for a cafeteria visit: jointly minimizing queueing time, food quality loss, and penalties for excessive speed.

Inequalities

1 note · 14 Sep 2026Subject page
  1. When exponentials get larger by exchanging the two parameters

    InequalitiesTypstPDF

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