Recent content by eccefeles

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    How do you rationalize fractions

    My apologies! I've made a big fool of myself once again. I was thinking about "realising" as in making the denominator of a fraction (containing complex numbers) real! (I was taught this term back in high school, here in Australia.) arildno and Hallsofivy are absolutely correct. I'm...
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    How do you rationalize fractions

    Fractions are already rational. Here's what "rational" means: http://en.wikipedia.org/wiki/Rational_number"
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    What are the key features to look for in an advanced calculus textbook?

    "Calculus: Single and Multivariable" by Hughes-Hallett et al? (I have no idea what is involved in the sophomore level. It's a first/second year textbook at my uni.)
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    How Do You Rationalize the Numerator with Square Roots in Limits?

    I hope I've understood your question: you wish to rationalise a surd (which is irrational)? No it can't be done. Would you like to rewrite the question in Latex? I'm not quite sure what it is that you're trying to do. Perhaps you are taking the wrong approach?
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    Physics or Electrical Engineering

    I am almost halfway through an engineering(electrical)/science (physics & maths) undergraduate double degree (Australian system if you're wondering). There are a few things I'd like to point out for ajsingh: 1> Many scientifically-inclined students find that the physics and mathematics in...
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    Why Are Women Underrepresented in Engineering Fields?

    I suppose it is difficult to analyse the fundamental differences in skills between the genders without having them skewed by external factors such as stereotyping and cultural norm. I really cannot see how researchers can satisfactorily account for these influences unless they raise a control...
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    MATLAB Solving for T3is in Matlab: Tips for Using XCount and Other Functions

    Alternatively you can vectorise all variables Since I have not used arrayfun before I do not know which is faster. p3=[2e5:1e4:10e5]; p2=1e5*ones(size(p3)); t2=288*ones(size(p3)); y=1.4*ones(size(p3)); t3is=t2.*((p3./p2).^(y-ones(size(p3))./y)); The dots in front of the operators...
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    Expressions used in change of variables

    OK, I accept there is no general approach. However, what about some "special" forms of f(x, y) and g(u, v)? I started pondering this question after I read about the Box-Muller method of generating random deviates with a Gaussian distribution from uniform deviates...
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    Distributions with Infinite Mean: Examples & Possibilities

    The Cauchy random variable (http://en.wikipedia.org/wiki/Cauchy_distribution" ) doesn't have a mean (or variance). I suppose that's different from having an "infinite" mean though.
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    Expressions used in change of variables

    Hi. I know the title is not very informative. Here's what I'm trying to do: I have f(x,y). I want to perform a change of variables to obtain a pre-defined g(u,v). How can I work out the actual expressions u(x,y) and v(x,y) so that it works out (including the Jacobian as well)? I have a...
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    How can I solve the current in a circuit quickly using Kirchhoff's Law?

    A good suggestion. However, http://mathworld.wolfram.com/CramersRule.html" is much easier.
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