Recent content by Data

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    Prime Numbers Formula: 1800s Math Discovery

    You can, of course, construct polynomials that will give you all the primes up to any arbitrary point, if you already know what they are!
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    Calculators Online app to replace Online TI-83?

    Your reply is a bit late. :wink: Still having a website that can perform calculator functions should not be that hard. I imagine flash can emulate the ti-83 online pretty well
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    What does actually research mean

    Of course, to mathematicians algebra refers not to simple symbolic manipulation but to a huge class of subjects. You can divide mathematics roughly into three branches (though there's so much overlap and so many topics that don't quite fit that this is not a great guide): Analysis, algebra, and...
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    Im soooooo close to solving this problem (Rings)

    You know m 1_R=0_R. You need to show that there are some x, y in R with x\cdot (n 1_R) = 0_R and (n 1_R) \cdot y = 0_R. I suggest trying y=x = \frac{m}{(n,m)}1_R. :smile:
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    Can You Solve This Hilarious Limit Problem Involving Sine and Infinity?

    ahahah, that one's good :smile:
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    Proof that sum of 3 roots of rationals is rational etc

    If \sqrt{c} is rational it's easy to see \sqrt{a}+\sqrt{b} must be rational. Then \sqrt{a} = r - \sqrt{b} where r is rational, ie. a = r + b - 2r\sqrt{b}, from which it follows that \sqrt{b} is rational (and the same argument shows \sqrt{a} must be rational as well).
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    Proof that sum of 3 roots of rationals is rational etc

    If \sqrt{c} is rational it's easy to see \sqrt{a}+\sqrt{b} must be rational. Then \sqrt{a} = r - \sqrt{b} where r is rational, ie. a = r + b - 2r\sqrt{b}, from which it follows that \sqrt{b} is rational, and from that it follows that \sqrt{a} must be rational as well.
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    Can You Solve This Hilarious Limit Problem Involving Sine and Infinity?

    Reminiscent of the ever-popular "There are 10 types of people: Those who understand binary, and everyone else."
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    Higher dimensions and symmetry

    If you think you've come up with something new, I encourage you to write it up in some cogent form. I'll be happy to read it! :smile: I am just trying to warn you that unless you spend some time with real mathematical and physical literature (in the form of textbooks, published articles...
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    Mathematica Masters in Mathematical Physics: Advancing Your Career with Specialized Training

    Indeed. While it's easy to say that highly theoretical courses are a priori harder than experimental stuff, there's one fact that breaks that argument completely, at least in my case: If I look at my audit (for a math-physics double honours degree), my grades in physics courses with a lab...
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    Higher dimensions and symmetry

    Yes, it is difficult to make visual representations of four-dimensional objects in 3- or 2-dimensional space (though it is certainly possible - see tesseracts and, for that matter, penteracts), and is quite perilous to try to visualize higher-dimensional objects; However, the arithmetic and...
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    How can I make x the subject of y = ~5/1-x?

    A square root is an exponent, though! \sqrt{a} = a^{\frac{1}{2}}. If you understand the rules for exponents then it's easy to see how to square a square root. :wink:
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    Prove Injectivity of x^x Function?

    Well, x^x = e^{x\ln x}, so it suffices to look at \lim_{x \rightarrow 0^+}{x \ln x} = \lim_{x \rightarrow 0^+}\frac{\ln x}{\frac{1}{x}}; Apply l'Hopital.
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    Programs Do I have what it takes to be a Math major?

    It sounds like you really are getting more into your math courses than your current major. What textbooks have you been using? I'd suggest picking up a few top-notch textbooks from the library; Say, Spivak's "Calculus," (this will cover things that you already know, but from a much more...
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    How can I make x the subject of y = ~5/1-x?

    White Rabbit: Consider \sqrt{2}. What's (\sqrt{2})^2?
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