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Mathematics
Quick fact
The epsilon-delta definition was formalized by Karl Weierstrass in the 19th century, finally eliminating the vagueness that plagued calculus since Newton and Leibniz.
Why this is interesting
You've probably heard that a limit is what the function 'approaches.' But what does 'approach' really mean? How close is close enough? The epsilon-delta definition answers this with a mathematical game of precision.
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Subjects · study & training · careers
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