Recent content by balingwhale

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    Spivak calculus ch.5 #24 delta epsilon proof for limit of peicewise function

    thanks a bunch but i think i had it in my last post. there will always be an x' that is closer to a than x and is not contained within one of the finite sets A_n.
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    Spivak calculus ch.5 #24 delta epsilon proof for limit of peicewise function

    what do you mean by the finitely many "big" values in the delta interval around a? so we're trying to say that x near a is never in the same set as a? and if we pick n to be very large then the sets become smaller? choose epsilon >= 1/n as before, s.t |x-a|< delta => |f(x)-0|=|f(x)|< 1/n...
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    Spivak calculus ch.5 #24 delta epsilon proof for limit of peicewise function

    thank you for your quick reply. to clarify, \varepsilon \geq 1/n? not \varepsilon \leq 1/n? further, should i suppose that a is in A_n? then either x near a is also in A_n and the limit = 1/n = 0 since n is large? or x near a is not also in A_n and the limit = 0. when will the...
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    Spivak calculus ch.5 #24 delta epsilon proof for limit of peicewise function

    Homework Statement Suppose A_n is, for all natural numbers n, some finite set of numbers in [0,1] and A_n intersect A_m={ } if m!=n Define f as follows: f(x) = 1/n if x is in A_n and 0 if x is not in A_n for all n. Prove that the limit as x goes to a of f(x) = 0 for all a in [0,1]...
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    Help is needed with physics of billiards

    breaking up impulse into components on the one side of the equal sign and final momentum into components (the sum of final momentums for each ball.. mv_A + mv_B +mv_C) on the other side of the equal sign will give us 2 equations. there are 3 unknowns. mass, impulse, angle theta are all given...
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    Help is needed with physics of billiards

    Homework Statement three billiard balls are arranged in an equilateral triangle formation labeled A, B, and C. the impulse which the cue imparts to the cue ball is a given, J, the angles at which the three balls will travel(depart from the stationary arrangement) can be easily found. i won't...
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