Recent content by nasshi

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    Integrating [itex]\frac{\partial f(x,y)}{\partial y(x)}[/itex] with respect to x

    Don't worry, it's... uh... already in the mail! :rolleyes:
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    Integrating [itex]\frac{\partial f(x,y)}{\partial y(x)}[/itex] with respect to x

    My original equation was taken from something with messy notation, and I lost some subscripts while working part of the larger question out. So I gave you a poorly framed question to answer -- I'm sorry. In my original question, the function f(x,y) is vector valued, and the integrand is...
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    Integrating [itex]\frac{\partial f(x,y)}{\partial y(x)}[/itex] with respect to x

    I don't know how to apply Leibniz's rule for this integrand. I believe there is a substitution to allow me to express this integral differently, but the partial being a function of what we're integrating by is confusing me. \int^{b}_{a} \frac{\partial f(x,y)}{\partial y(x)} dx Knowns are that...
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    Explaining the trick of using [itex]g(x)=f(x+1)[/itex] to show irreducibility

    So as an example, if defining g(x)=f(x^{2}+45x-2) and Eisenstein's criterion showed that g(x) is irreducible, then f(x) is irreducible? Or can I only use linear factors such as g(x)=f(x-2)?
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    Explaining the trick of using [itex]g(x)=f(x+1)[/itex] to show irreducibility

    This is for clarification of a method. Dummit & Foote, pg 310, Example (3). f(x)=x^{4}+1 is converted into g(x)=f(x+1) in order to use Einsenstein's Criterion for irreducibility. The example states "It follows that f(x) must also be irreducible, since any factorization of f(x) would...
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    Prove [itex]f(x)=\sqrt{x^{2}+1}[/itex] is uniformly continuous on the real line.

    So there's no hangup working on the whole real line from the start due to the derivative being bounded? I was unsure about using the MVT in a more general setting.
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    Prove [itex]f(x)=\sqrt{x^{2}+1}[/itex] is uniformly continuous on the real line.

    Homework Statement Prove f(x)=\sqrt{x^{2}+1} is uniformly continuous on the real line. Homework Equations Lipschitz Condition: If there is a constant M such that |f(p) - f(q)| \leq M |p-q| for all p,q \in D, then f obeys the Lipschitz condition. Mean Value Theorem: Let f be continuous on...
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    Analyzing Line Integral over Non-Exact Region |x|+|y|=4

    I found the fundamental property regarding splitting up piecewise smooth curves two chapters earlier, which I need to review. I got an answer of -\pi, which is what the solutions suggested. Thank you very much!
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    Analyzing Line Integral over Non-Exact Region |x|+|y|=4

    Can this be done finitely many times as long as the pieces form a closed curve when put together? Are there other stipulations for breaking apart the curve to work, or onlyclosure of the curve?
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    Analyzing Line Integral over Non-Exact Region |x|+|y|=4

    Analyzing an integral over a non-exact region for gamma defined by |x|+|y|=4 The following was similar to a problem on a calculus final that I got wrong. It is an extension of a problem in R.C. Buck "Advanced Calculus" on page 501. Similar to knowing the trick to integrating e^{|x|} (which...
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    Writing a r.v. in set notation

    The definition I have for a random variable is X=\lbrace \omega \in \Omega \vert X(\omega) \in B \rbrace \in F where F is a sigma algebra and B is a Borel subset of R. Using function composition, how would one write a similar set notation definition for f(X), where f is a Borel measurable...
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    Examples of taking limits of intervals

    HallsofIvy, I'm trying to show that for F_{n} \subset F_{n+1} for all n (they're sigma-algebras), that \cap ^{\infty}_{i=1}F_{i} may not be a sigma algebra. Counter example is what the exercise says. I was thinking of a sequence of intervals that never include 0. But I didn't know how to...
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    Examples of taking limits of intervals

    I guess I've fallen through some of the cracks in the plethora of definitions I've learned, or I just never had enough examples of taking limits of intervals. Anyways, which is true, and why? $\cap^{\infty}_{n=1}(0,\frac{1}{2^{n-1}}]=0?$...
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    Optimizing Inequality with Constraints

    I can't exactly "fix my constraints". I'm trying to prove something as generally as possible. Can you think of any constraints I can add that would easily establish the desired result? Because I can't.
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