An accumulation point, or limit point, for a set S is a point x (not necessarily in S) such that any open set containing x also contains a point (distinct from x) that's in S. More intuitively, it means that by choosing points in S, we can get as close as we want to x without actually reaching it. For example, consider the set S={1,1/2,1/3,1/4,...} (in the real numbers). 0 is an accumulation point for S, because any open set containing 0 would have to contain all between 0 and some ε>0, which would include a point (actually, an infinite amount of points) in S. But 1/5, for example, is not an accumulation point for S, because we can take the open interval (11/60,9/40) which doesn't contain any points in S other than 1/5. Not all sets have an accumulation point. For example, any set of a finite amount of real numbers can't have an accumulation point. Another example of a set without an accumulation point is the integers (as a subset of the real numbers). However, over the real numbers, any bounded infinite set has an accumulation point. In a general topological space, any infinite subset of a compact set has an accumulation point.
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There are several meanings to the word 'calculus.' The plural for calculus is 'calculi.' There is no plural for the calculus we use in mathematics.
My Calculus class is in third period. Calculus is a noun
Im still taking Integral Calculus now, but for me, if you dont know Differential Calculus you will not know Integral Calculus, because Integral Calculus need Differential. So, as an answer to that question, ITS FAIR
there was no sure answer about who started calculus but it was Isaac Newton and Gottfried Wilhelm Leibniz who founded calculus because of their fundamental theorem of calculus.
calculus that is intermediate in difficulty