Recent content by Atropos

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    Difficult(?) convergence problem

    Wow, I'm an idiot. I was so hung up on the cosine part of the sum that I completely forgot about the monotonic series u_n. I was only paying attention to the fact that cosine was sinusoidal ad therefore f_n>f_n+1>0 couldn't apply. ...but it does apply to u_n. Thank you for pointing that...
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    Difficult(?) convergence problem

    Homework Statement Show that if \vartheta is any constant not equal to 0 or a multiple of 2\pi, and if u_{0}, u_{1}, u_{2} is a series that converges monotonically to 0, then the series \sum u_{n} cos(n\vartheta +a) is also convergent, where a is an arbitrary constant. Homework...
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    Will This Infinite Series Converge or Diverge?

    Are you sure the summation is from 0 to \infty, because ln(n) doesn't exist for n=0. Maybe it's supposed to be a trick question?
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    Solving Vector Calculus: (a+2b)∇(∇⋅u) - b∇x∇xu - (3a+2b)c∇T(r)=0

    i know that \nabla(\nabla\bullet\vec{u}) - \nabla\times\nabla\times\vec{u} = \nabla^{2}\vec{u} i dunno, what about this?.. Solve this equation for \nabla\times\nabla\times\vec{u}, then substitute into your equation, and simplify the resulting equation. The first term of your equation...
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    Undergrad Techniques of Integration [need feedback]

    Integration of the series expansion and contour integration are pretty useful. Laplace transforms too. There's also the Howitzer Cannon of integration techniques: differentiation with respect to a parameter.
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    Why do wheels not topple over while rolling?

    \vec{}Forget what I wrote in my last post. I think I found a way to solve this using only algebra. Let me sum up the problem as I understand it. Let me know if it's correct or not. **A circular disc of uniform density, mass M and radius R is rolling without slipping on the ground. Initially...
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    Why do wheels not topple over while rolling?

    im having issues with LaTeX
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    Why do wheels not topple over while rolling?

    There's no force that restores the wheel to its upright position, but there is a force that resists any change in the position. Before we can figure out what that force is, we need to make a few assumptions. (1) Because the wheel is rolling, it is rotating about a fixed axis, so it has angular...
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    The best textbooks in their subjects are ?

    As this my first post, I'm not sure if this is the right place to ask this question. But textbooks are learning materials, so I think it's alright. I enjoy learning new things in math, but textbooks are very expensive. I'd really hate to spend $100+ on a book, only find out that it isn't...