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Mathematics
Quick fact
The epsilon-delta definition of a limit, first rigorously formulated by Karl Weierstrass in the 19th century, eliminated centuries of vague reasoning in calculus and made it a truly logical discipline.
Why this is interesting
You can get as close as you want to a target, but how close is close enough? The epsilon-delta definition turns that fuzzy idea into a mathematical precision game.
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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.
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