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FACTREE gives you something interesting to discover every day — and something worth talking about together.
Start with one fact. Explore it, go deeper, then follow whichever branch catches your imagination.
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Mathematics
Quick fact
The epsilon-delta definition was formalized in the 19th century by mathematicians like Weierstrass, and it allowed calculus to be placed on a fully logical foundation, removing the need for 'infinitely small' quantities that were previously mysterious.
Why this is interesting
You've been told a limit is 'what the function approaches'—but what if it doesn't 'approach' in the way you imagine?
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Subjects · study & training · careers
Choose something you are considering. FACTREE will give you a clear picture of what it contains, how its main parts connect and where it could lead.
This private catalogue connects 31 subjects, study routes and careers across six broad areas. Public Maps and learner routes remain off.
Browse subjects
Open a subject to see its complete shape at a glance. You can always return here and choose something else.
See what programming involves, how its main areas connect, and whether you find the knowledge interesting enough to take it further.
Structuring the Programming Map…
Complete subject map
Move from the one-screen overview into all 19 areas. Open any area, compare possible Paths and return to the overview whenever you want.
Loading the complete Programming Map…
Curiosity quiz
One question at a time. A wrong answer is simply another way into something worth knowing.
Administrator
Review learner demand, card visibility and private knowledge-architecture evidence.
Knowledge architecture
This background view organises existing cards. It is separate from the authored lessons above.
Review public suggestions and repeated searches. Approval alone does not add generator tasks.
Hide a published card reversibly, then optionally queue it for a reviewed merge or permanent retirement.
Curriculum coverage
Discovery cards in this subject
