Recent content by julypraise

  1. J

    Is Fitzpatrick's Advanced Calculus the Best Book for Multivariable Analysis?

    quite a late reply I write this answer on 2013, so it is quite late but I still hope this be helpful. I know a book that can definitely satisfy you. It is Advanced Calculus by Fitzpatrick. I've recently read Munkres's and Duistermaat's. The former one is very very good. It is...
  2. J

    Algebraic Topology: Connected Sum & Reference Help

    Thanks mathwonk. I will definitely keep in mind your insight and comment when I study this in a more rigorous setting. And thanks Bacle2. Indeed the quotient topology section in Munkres seems quite good; it does not use that fluffy method in the proof.
  3. J

    Algebraic Topology: Connected Sum & Reference Help

    Thanks for the reply mathwonk! I actually thought I wouldn't get any answer, anyway thanks. Okay as for the textbooks that you'v recommneded, I would look them up. But I'm very new to this topic. So obviously I haven't read them at all. Actually I'm not even really studying 'real' algebraic...
  4. J

    Algebraic Topology: Connected Sum & Reference Help

    I was working on some algebraic topology matters, thinkgs like the connected sum of some surfaces is some other surface. And for this study, I was using the Munkres's famous textbook 'Topology' the algebraic topology part. My qeustions are as follows: Q1) Munkres introduces 'labelling scheme'...
  5. J

    A measure related with Reimann integral

    Thanks for your answer, and as you have told me I should assume that f(x) \geq 0 a.e.. And for the last part you mentioned, I think Dominated Convergence Theorem would suffice, woudn't it? I used it in my solution..
  6. J

    A measure related with Reimann integral

    Homework Statement Let ( \mathbb{R}^k , \mathcal{A} , m_{k} ) be a Lebesgue measurable space, i.e., m_{k}=m is a Lebesgue measure. Let f: \mathbb{R^k} \to \mathbb{R} be a m-integrable function. Define a function \mu : \mathcal{A} \to [0,\infty] by $$ \mu(A) := \int_{A} f(x) dx $$ with A \in...
  7. J

    Error function (defined on the whole complex plane) is entire

    Ah.. frankly I'm not sure of how to expand by Taylor series... Is it by using Cauchy's Theorem? Could you give me any reference textbook where I can look up the theorem for this Taylor series expansion?
  8. J

    Error function (defined on the whole complex plane) is entire

    Homework Statement The wiki page says that error function \mbox{erf}(z) = \int_{0}^{z} e^{-t^{2}} dt is entire. But I cannot find anywhere its proof. Could you give me some stcratch proof of this? Homework Equations The Attempt at a Solution I've tried to use Fundamental Theorem...
  9. J

    Gamma Function Limits: Proving \Gamma(x) \to 0 as x \to -\infty

    Ah... MY BAD! sorry.. what was I thinking... Let me clarify once more: Take x_{n} \in (-n,1-n) . Then \Gamma (x_{n}) \to 0 as n \to \infty . I think I have an idea to solve it without using Gauss's Formula. After I try, I will put on the thread. Anyway thanks for reminding me.
  10. J

    Gamma Function Limits: Proving \Gamma(x) \to 0 as x \to -\infty

    Ah.. I know what you mean. Maybe I need to modify my problem first. I know it has poles on non-positive integers. But excluding poles, it seems the absolute value of the gamma function tends to zero as x \to - \infty . (http://en.wikipedia.org/wiki/File:Complex_gamma_function_abs.png) May I...
  11. J

    Gamma Function Limits: Proving \Gamma(x) \to 0 as x \to -\infty

    Homework Statement The absolute value of the gamma function \Gamma (x) that is defined on the negative real axis tends to zero as x \to - \infty . Right? But how do I prove it? Homework Equations The Attempt at a Solution I've tried to use Gauss's Formula...
  12. J

    Proof Error Q. Conway's Functions of One Complex Variable VI

    Okay.. I think by your notion it seems very plausible to conclude that \lim_{n\to\infty}\frac{f(z_{0}+h_{n})-f(z_{0})}{h_{n}}=\lim_{h\to0}\frac{f(z_{0}+h)-f(z_{0})}{h} though I'm not using Thm 4.2 in Baby Rudin But what about...
  13. J

    Proof Error Q. Conway's Functions of One Complex Variable VI

    Ah of course yes, baby Rudin does not use sequences in his proof (in his latest edition). And Rudin's proof is very clear whereas Conway's seems not valid. As for the lemma, doesn't that lemma state that 'limit exists iff for an "arbitrary" sequence the sequential limit exists'...
  14. J

    Proof Error Q. Conway's Functions of One Complex Variable VI

    I ask this question only to those who read or have this book: If you have Baby Rudin, it would be even better. On the page 34 of the text Conway's Functions of One Complex Variable Vol 1, it proves the Chain Rule but it seems the proof is not valid: It uses sequences to show the limit is...
  15. J

    Finding Errors in Proof for Baby Rudin Problem 2.7

    Oh yeah. I think I know what you mean. i_{0} depends on epsilon. Thanks.
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