Recent content by Big-T

  1. B

    Proving Integral of x^x Does Not Exist

    How about letting x^x = e^{x\ln x} ?
  2. B

    Proving Integral of x^x Does Not Exist

    http://www.sosmath.com/calculus/integration/fant/fant.html
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    Submersion and fiber bundles

    How would one go about to construct a function on (smooth) manifolds that is a submersion without being (the projection map of) a fiber bundle?
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    Contour Integration: Solving Homework Statement

    What contour have you used? Could it have something to with the choice of brance of the square root function?
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    Is sin-1(2i) Equal to 0.5 + 1.31696i?

    For the two last posts, isn't it supposed to be (y - 1/y)/2i = 2i ?
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    Harmonic movement of a spring question

    Imagine the unit circle projected onto the y-axis, then pi/4 corresponds to 1, 0 and pi to 0 and -pi/4 to -1 as initial positions.
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    Harmonic movement of a spring question

    Your initial conditions gives these equations, from which you should be able to retrieve u: r(t)=Asin(wt+u) r(0)=A
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    Is C > R? Complex vs Real Set Size

    Marcus' function would be well defined if we agreed to use trailing nines wherever the decimal expansion is terminating, this should of course have been specified.
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    Two vector spaces being isomorphic

    How many basis vectors do you need to span P_k?
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    Is C > R? Complex vs Real Set Size

    How could that possibly be a bijection? Obviously, z_1=a+ib is mapped to the same point as z_2=a z_1, so it is not an injection. Marcus has already provided a valid bijection, his "decimal merging" is the classical example of this. Notice how it is also valid in \mathbb{R}^n.
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    Mastering PDEs: Solving the Non-Constant Coefficient d^2G/dxdy Equation

    What RedBranchKnight refers to is a special case of the http://en.wikipedia.org/wiki/Method_of_characteristics" .
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    What is the derivation of pi and how is it defined?

    Rudin defines pi/2 to be the smallest positive number such that cos(pi/2)=0.
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    First order pde cauchy problem by method of characteristics

    You may have a look here: http://en.wikipedia.org/wiki/Inverse_trigonometric_function#Logarithmic_forms"
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    Understanding the Multiplicity of Poles in Complex Analysis

    That definition put everything in place, thanks!
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    Understanding the Multiplicity of Poles in Complex Analysis

    I.e. the multiplicity is the power of the term with the largest negative power in the laurent series of the function? Does this also mean that an isolated/(essential?) singularity is a pole with infinite multiplicity?
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