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COMPLETE INDEX

15 notes across 3 tracks and 10 subjects, newest first.

Last note added 31 Oct 2026 · back to the overview

Mathematics

11 notes in 6 subjectsTrack page

Structure, space and change, developed from definition to proof.

Real analysis

3 notes · 18 Sep 2026Subject page
  1. Here we discuss how quickly the infinite product of sums of squares increases.

  2. Provide a new way of defining e from the tangent-line inequality.

  3. 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

2 notes · 30 Oct 2026Subject page
  1. Taylor Form

    Properties of so-called Taylor Forms, which are close to jet bundles.

    GeometryTypstPDF
  2. 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.

Inequalities

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

    InequalitiesTypstPDF

Problems

3 notes · 31 Oct 2026Subject page
  1. IMO 1992 P2

    A solution for IMO 1992 P2

    ProblemsTypstPDF
  2. IMO 2002 P5

    Two solutions for IMO 2002 P5

    ProblemsTypstPDF
  3. A technique for solving a functional equation with finitely many ratios

    ProblemsTypstPDF

Physics

3 notes in 3 subjectsTrack page

Mechanics, fields and quanta, with the mathematics each of them demands.

Dynamics

1 note · 24 Sep 2026Subject page
  1. Analyze the sling by projection on the y-axis.

    DynamicsTypstPDF

Statics

1 note · 24 Sep 2026Subject page
  1. Derive the form of the catenary using the infinitesimal method.

    StaticsTypstPDF

Kinematics

1 note · 25 Sep 2026Subject page
  1. Relationship between horizontal velocity and vertical velocity in horizontal projection with resistance.

    KinematicsTypstPDF

Modeling & computation

1 note in 1 subjectTrack page

Optimisation, simulation and numerical models, with every assumption stated up front.

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.

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