Recall Drill

Reading a derivation and being able to reproduce it are different skills, and the gap between them is almost entirely a retrieval problem. You understood the spectral theorem on Tuesday; on Friday you cannot state it. Nothing went wrong — that is simply what memory does to material you have read once and never had to pull back out.

This page is the pulling-back-out.

How it works

Every page in this module ends with a recall card: a handful of bullets naming what you should be able to state without looking. This deck is built from those bullets automatically, so a prompt here can never say something the page does not.

Each prompt comes in one of two shapes:

• A cue. You see a short label — “reduced row echelon form”, “complementary slackness” — and recall what it means.
• A cloze. You see a sentence with the claim removed and recall the claim.

Grade yourself honestly, in three buttons:

grade	means	when you see it again
again	you did not have it	tomorrow, and the ladder resets
hard	you got there, slowly	same interval as last time
good	it came straight back	one rung further up the ladder

The ladder is 1, 3, 7, 16, 35 days. Nothing is stored on a server; your progress lives in your own browser, and it is shared with the DSA drill deck if you use that one too.

Three keys

Space reveals the answer, then 1, 2, 3 grade it. Drilling with the mouse is slow enough that most people stop doing it, which is the only real failure mode here.

Use it like this

Not as a first pass. A prompt you have never seen the derivation for is just a riddle. Read the page, do its exercises, and let the card come back to you two days later.

Do drill across chapters rather than within one. Recognising that “this is a projection argument” when the question does not mention projections is the skill that matters, and a chapter-scoped deck never tests it. Leave the filter on every chapter unless you are revising for something specific.

Do follow the link on a card you got wrong. Every prompt carries the page it came from. A prompt you fail twice is not a memory problem, it is a comprehension problem, and re-reading beats re-drilling.

The deck

Every chapter (513 prompts)00 · Getting Ready01 · Introduction and Motivation02 · Linear Algebra03 · Analytic Geometry04 · Matrix Decompositions05 · Vector Calculusdue only513 due · 0/513 seen · 0 mature

Vector Calculus Overviewcloze

____ — One more index and everything is "a tensor", which is precisely where Section 5.8 stops being practical.

Reveal space

0 graded this sessionReset schedule

When a chapter is what you need

Each chapter overview page carries the same deck scoped to that chapter, for the evening before an exam on one topic. The full deck above is the one to use the rest of the time.

If the deck looks empty

It is generated, not written, so it is rebuilt from the pages by:

bash

npm run mml:recall

A page contributing nothing means its ## Recall card section is missing or its bullets are not bold-led. That is a bug in the page, and the generator names the file.