Recent content by hello95

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    Unpaid internship versus Research over the summer

    Hello, I am a math and statistics double major, and basically I have a guaranteed unpaid internship opportunity this summer. I have yet to send out applications to other organizations/REUs. While I am interested in the long term in consulting/finance and industrial modeling, I hope to get...
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    Problem A1 from the 2009 Putnam Exam

    Ah, I see what you're saying. Thank you for the response, I guess my solution wasn't as elegant as I had thought haha. Even if I was able to show that the equations were nontrivial it would end up being a lot more complex than the official solution.
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    Problem A1 from the 2009 Putnam Exam

    That's from page 67 of Multivariable mathematics (4th edition) by Williamson and Trotter.
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    Problem A1 from the 2009 Putnam Exam

    Here we go: "A homogeneous system Ax = 0 has only the zero solution if Ax = 0 has at least as many nontrivial equations as variables."
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    Problem A1 from the 2009 Putnam Exam

    I apologize if I'm wrong, I haven't done much work with matrix algebra as I have only taken theory-based linear algebra (Axler).
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    Problem A1 from the 2009 Putnam Exam

    Well each entry will be 1 or 0, and each combination of 1s and 0s in each row will be different, because each square is unique. There will be 4 1's in each row. Wouldn't that imply that you cuold put the matrix into eschelon form, solving for each a(i)?
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    Problem A1 from the 2009 Putnam Exam

    Here is the problem: Let f be a real-valued function on the plane such that for every square ABCD in the plane, f(A) + f(B) + f(C) +f(D) = 0. Does it follow that f(P) = 0 for all points P in the plane? Below is my solution: Create a 3x3 set of boxes (where each box has equal...
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    Solving the 8 Pawns Puzzle on an 8x8 Chess Board

    Wikipedia says that there are 92 ways of solving the problem though, so I don't know.
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    Solving the 8 Pawns Puzzle on an 8x8 Chess Board

    well come to think of it, each queen eliminates two diagonals, so I'm not sure it would ever work
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    Solving the 8 Pawns Puzzle on an 8x8 Chess Board

    Actually I'm not sure if it does work now that I'm trying to work it out... each queen eliminates a row, column, and diagonal from future options of where to place the next queen. Eventually the eliminated columns and diagonals amount to eliminating a row no matter how you place the first 4 or 5...
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    Solving the 8 Pawns Puzzle on an 8x8 Chess Board

    ^I remember that problem. It's possible if I remember correctly
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    Solving the 8 Pawns Puzzle on an 8x8 Chess Board

    D wasn't really meant to be a function by the way, just a way of signifying the concept
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    Solving the 8 Pawns Puzzle on an 8x8 Chess Board

    so are we talking a series of pawns (p(1), p(2), ... , p(8)) such that D(p(i)) - D(p(i + 1)) is different for every i? Because something like a conch shell spiral works if that's the case. More generally I think with any nxn board it should be possible to place n pawns at different distances...
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    Jeans Mass Formula - Find Solution Now!

    Equate gravitational potential energy with kinetic energy of the gas for a given radius and density, and then find the mass from that.
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    How many dimensions is this vector space?

    So I just got out of my linear algebra midterm, and this question is confusing the hell out of me. Basically, it's a subspace of R^4, such that the coordinates satisfy the following qualifications: (a, b - a, b, 2(b - a)) So basically, a and b can range over the xz plane, and y and w sort...
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