Recent content by Whatever123

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    Lim x^{1/x}, x-> infty

    To the people arguing the limit of ln(x)/x as x ---> infinity... that's just 0. Using l'hoptial's rule yields 1/x/1 = 1/x which goes to 0 as x goes to infinity...
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    Similar Matrices & Geometric Multiplicity

    Yes, I understand now. Thank you for your help. I figured out the first part and just needed that little hint to help me with the rest!
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    Solving a Second-Order Differential Equation with Variable Coefficients

    What's the point of the 2's? I would have just canceled them out from the beginning. (Y*Y'')/Y' = -X (Y''/Y')(Y) = -X Set P = Y', then: (P'/P)Integral(P) = -X Ok, I'm sorry. This is going nowhere. Given me 24 hours to think about it.
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    Similar Matrices & Geometric Multiplicity

    So now that I've proven that A, B have same eigenvalues \lambda1-\lambdan and that they appear the same amount of times, consider the eigenvectors for those eigenvalues. As you said, let x be an eigenvector of A. Need to show that Cx is an eigenvector of B with the same eigenvalue... If x is...
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    Similar Matrices & Geometric Multiplicity

    Homework Statement Prove that if two matrices are similar then they have the same eigenvalues with the same algebraic and geometric multiplicity. Homework Equations Matrices A,B are similar if A = C\breve{}BC for some invertible C (and C inverse is denoted C\breve{} because I tried for a...
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    Proving Inequalities: Multiplying 2 Negs Becomes a Positive

    Yes. That was an original typo mistake that I simply missed. I updated it when I responded to you.
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    Proving Inequalities: Multiplying 2 Negs Becomes a Positive

    I'm saying that it doesn't matter in my proof because I do not care what the actual value is; I just care about if it's greater or less than 0. I'm just worried about the signs, not the value. So it does work out the same for my proof.
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    Proving Inequalities: Multiplying 2 Negs Becomes a Positive

    I divided because it doesn't really make a difference to the proof and it's easier on me. I wanted to show that a/((-b)(-c)) > 0. Since the numerator, by definition, is greater than 0, then the denominator must be greater than 0. I thought it would be an easy way to look at it since you're...
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    Proving Inequalities: Multiplying 2 Negs Becomes a Positive

    Doesn't matter... It works out the same... Thanks for the advice... I'll keep that in mind when trying to expand my current proof...
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    Proving Inequalities: Multiplying 2 Negs Becomes a Positive

    Ok... So today, someone asked me a simple question: Why do two negatives become a positive number when multiplied together? This is intuitively basic, but not as easy to prove (unless there's some simple proof that I didn't think of). This was the basic proof that I came up with: Let a, b, c >...
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    Have you experienced the enlightening Feynman Lectures on Physics?

    Yeah, that seems to be the popular response from people on other forums also. Not one person has said anything bad about them yet. I'll probably pick them up this Thursday unless someone gives me a good reason not to...
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    Have you experienced the enlightening Feynman Lectures on Physics?

    Has anyone read the Feynman Lectures of Physics*? I've heard about them and they seem pretty nice. I'm thinking of looking into them but wanted some feedback from someone who has already read them. I already know some of the basics and so I mainly wanted these to better my understanding of...
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    Math I want to succeed in a career in science, but i am not a math genius

    If you're only 17, you may grow to love math. I love math but didn't at your age... I thought math was useless and pretty boring. I was good at it. I got A's throughout high school (and I was a terrible student, yet still got A's in math). If you told me that some day I'd like it I would have...
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    Discussing Probability & Odds: Does Flipping More Cards Increase Chances?

    Well... You're entitled to your opinion and you, of course, do not have to agree. But unfortunately for you, mathematics is not about opinion and just because you do not agree doesn't mean that you're any less wrong.
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    Discussing Probability & Odds: Does Flipping More Cards Increase Chances?

    You just don't get it, do you? I already explained this once. You have a 1/52 chance at the beginning of it being an ace of spades, but you also have a 1/52 chance of it being an eight of hearts. So at the end, it's 50/50 because 1/52=1/52. Even basic logic disproves what you're saying because...
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