Recent content by phantomcow2

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    Method of undetermined coefficients

    Awesome. Thanks for the helpful responses -- I solved the differential equation and plugging in A*T instead of just "A" worked. I recall my professor mentioning that once during class. I realize why my original guess wasn't a solution, too.
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    Method of undetermined coefficients

    y''+9y=sin(3t) I need to solve the above using the method of undetermined coefficients. I have already found the solution to y''+9y=0 is c1(Cos3t)+c2(sin3t). The problem is finding the particular solution. From class I am aware that the general form of the solution is...
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    Determine location of structural break in cross-section data

    I'm trying to run a simple regression for a data set (n=165). I've determined via a Chow Test that there exists a structural break somewhere; the same least squares estimate cannot be accurately used to represent the entire range of values the explanatory variable takes on. I've found two very...
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    Find length of two line segments in parallelogram.

    Awesome, actually that did help :p. Sometimes it's the simple things that are overlooked.
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    Find length of two line segments in parallelogram.

    Homework Statement ABCD is a parallelogram with <BAD=60. Lines AM and BM bisect Angles BAD and ABC respectively. Perimeter of ABCD is 6. Find lengths of the sides of triangle ABM. [PLAIN]http://img709.imageshack.us/img709/2440/stumped.jpg The Attempt at a Solution I'm stumped...
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    Math preparation for business school?

    My question isn't related to natural sciences as most in this forum are, so I'm not sure this is the appropriate place to ask. I'm an undergrad junior (almost a senior) and am considering business school a few years down the road. I'm wondering, though, what kind of math should I have taken to...
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    Having difficulty understanding what the Range of a linear transformation is.

    Wow, that is a wordy explanation and exactly what I needed. Thanks :).
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    Having difficulty understanding what the Range of a linear transformation is.

    One of the topics in my linear algebra course is kernel and range of a linear transformation. I have a firm understanding of what the kernel is: the set of vectors such that it maps all inputs to the zero vector. Range, however, remains nebulous to me. My textbook says that the range is "THe...
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    Is the force of gravity a function of a planet's orbit?

    Wow, thanks for the helpful replies! :). ehild, it turns out that your derivation was one that was gone over in class during the one time I wasn't there :p (I had a medical appointment). I found notes from a classmate and to sum it up the resulting formula is \frac{-mr_{0}^2v_{0}^2}{r^2}...
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    Is the force of gravity a function of a planet's orbit?

    Kepler's 2nd law says that the rate at which the radius vector sweeps area is constant. That is, the orbiting planet will adjust it's velocity accordingly to ensure that this is so. I'm not sure what the connection is between this and gravity is though.
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    Is the force of gravity a function of a planet's orbit?

    I don't think the professor is suggesting that this is a plausible orbit. For what it's worth, this is a problem given to me in a class called History of Mathematics -- it's not a physics class.
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    Is the force of gravity a function of a planet's orbit?

    That'd be great. I'd be interested in knowing how to derive it. I'm surprised I can't find anything about this online.
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    Is the force of gravity a function of a planet's orbit?

    Ugh, I was afraid of that. My professor is old fashioned and doesn't use textbooks for any of his classes. I've scoured the internet and my notes and haven't found mention of non-elliptical orbits.
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    Is the force of gravity a function of a planet's orbit?

    Here's the exact wording of the problem: "Suppose that in a universe where Kepler's second law holds, a planet revolves around the sun on the path with polar eq r= 1 + sin(theta). When theta = pi/2, the velocity vector and position vector are perpendicular to one another. Calculate the...
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    Is the force of gravity a function of a planet's orbit?

    The problem says that the orbit isn't an ellipse, though. It's defined by r=1 + sin (theta).
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