Recent content by foo_daemon

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    Projectile motion: solving for variable angle

    Hm, I still had problems finding the solution. I 'cheated' and used WolframAlpha to solve that last formula for theta. Wolfram uses substitution and gives: \theta = tan^{-1} \left ( \frac{ -V_i^2 \pm \sqrt{-g^2 x^2 + 2 g H V_i^2 + V_i^4}}{gx} \right ) WolframAlpha then states that...
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    Projectile motion: solving for variable angle

    Aha... yes, I didn't really want to solve for t, I just didn't see a way around it. Your approach is simple, and I'm dumbfounded I didn't realize it first ;) However, it still seems to be an involved problem. Now we have: t = \frac{x}{V_0} Plugging this t into the formula for V_y, I...
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    Projectile motion: solving for variable angle

    Hi, I've been muddling over this problem for a few days. I thought there would be a simple approach, but I'm having trouble reaching a solution. Here is the rundown: We have a 2D projectile launcher. It hurls an object from the origin (0,0) at some initial velocity with magnitude V_i at angle...
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    An efficient way to find perfect squares?

    Wow, was just testing around and it appears the exact same recursive formula satisfies the second part of the equation as well (the 'conjugate' square, I guess you could call it?). You just need to use the different set of initial values: n_i = 1, 5, 65, 901, 12545... m_i = 0, 8, 112...
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    An efficient way to find perfect squares?

    RamaWolf: Haha, nice! Yep, you identified where this problem stems from (I was sort of partitioning it up): http://projecteuler.net/index.php?section=problems&id=94 To find integer areas of the isosceles triangle \left( n, n, n-1 \right) one must solve (expanded from Heron's formula):Area =...
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    An efficient way to find perfect squares?

    Hi, I have a problem that I'm a bit stuck on, and need some direction: I need to find \forall_n within a certain domain that can satisfy this equation: \left( 3n-1 \right) \left( n+1 \right) = m^{2} where m,n \in \mathbb{Z} Or, to put it in a different context, I'm looking for...
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    Proof of lim (n)^(1/n)

    Homework Statement Prove the \lim_{n\to +\infty}{\sqrt[n]{ n! }} \equiv \infty Homework Equations uses well-known operations The Attempt at a Solution I think the best (easiest) approach is to find some f(n) \leq n! , and express it as some g(n)^{n} . This will then get rid of the...
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    Solving the Integral of x^log(x): How to Approach?

    Hi, I need to solve the following integral from 0 to \infty : Please note that my professor has defined log(x) = ln(x) , i.e. 10 is not the default base. \int { e^{\frac{-log(x)^2}{2} } dx } Through 'simplification' ( e^{log(x)} = x ), I have translated the function to: \int { x^{...
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