Recent content by ironspud

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    Showing a relation is a partial order on a set

    Nevermind. I just spoke with my professor. Seems I was just over thinking everything. Still, if anyone would like to provide some insight to part (b), I'd appreciate it.
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    Showing a relation is a partial order on a set

    Homework Statement Okay, so here's the problem: (a) Let U be a universal set and suppose that X,Y\in U. Define a relation,\leq, on U by X\leq Y iff X\subseteq Y. Show that this relation is a partial order on U. (b) What problem occurs if we try to define this as a relation on the set...
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    Find the inverse of f if f(x) = x^2 - 8x + 8 and x is less than or equal to 4

    Homework Statement Find f^{-1}(x) if f(x)=x^{2}-8x+8 and x\leq4 The Attempt at a Solution I set y=x^{2}-8x+8, and then switch y and x to get x=y^{2}-8y+8. I then try solving for y, but I end up with y's on both sides of the equation: x=y^{2}-8y+8 x-8=y^{2}-8y x-8=y(y-8)...
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    HW Check: Prove that the sequence {a_n} converges to 1/2

    Yeah, I figured there was no problem in the substitution, though, maybe I should have provided the reasoning behind it in the proof. Oh well. Anyway, thanks again.
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    HW Check: Prove that the sequence {a_n} converges to 1/2

    Thanks dynamicsolo. And, yeah, I get the substitution by knowing \frac{1}{2\sqrt{n^*}+1}<\epsilon. Solving for epsilon, [\frac{1}{2}(\frac{1}{\epsilon}-1)]^2<n^*. And since n\geq n^*>[\frac{1}{2}(\frac{1}{\epsilon}-1)]^2, then...
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    HW Check: Prove that the sequence {a_n} converges to 1/2

    Hi, Just hoping someone could check my work and point out any errors, if any. Homework Statement Consider the sequence {a_n} defined by a_n=\frac{n}{2n+\sqrt{n}}. Prove that \lim_{x\to\infty}a_n=\frac{1}{2}. (Do NOT use any of the "limit rules" from Section 2.2.) Homework Equations A...
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    Determine the negation of the expression

    If you look at a truth table for a conditional statement such as P\rightarrow Q, you should find that the only time this statement is rendered false is if the antecedent (the first part, P) is true and the consequent (the second part, Q) is false. So, what does that tell you about your...
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    Induction proof involving arbitrary intersections/unions

    No. I don't think so. I mean, I get what you're saying. I just don't think I have the tools to prove something like that - i.e, I don't know how to represent or manipulate statements like that symbolically.
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    Induction proof involving arbitrary intersections/unions

    Yay. Thanks. Question, though. What would be the difference between what I said I was asked to prove - i.e, "arbitrary unions/intersections" - and what I was actually asked to prove? I know that's probably a really stupid question but, like I said, I've never taken any sort of...
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    Induction proof involving arbitrary intersections/unions

    Hi, So, I was assigned a problem in my Intro Analysis course that involves proving, by induction, that the set A minus some arbitrary number of intersections of the sets B_{j} is equal to some arbitrary number of unions of A minus the sets B_{j}. I've written out a proof, but I'm not too...
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