Recent content by Gackhammer

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    Differential Equation with Function of Shifted Variable

    Hey guys, I have a question for you... how would one go about solving an equation like this... or this... This came across my mind the other day. I was wondering how to solve that equation if the function is of t-1, instead of t. Obviously, if it was f(t), the solution would be Ce^t, but I was...
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    How can I rotate a coordinate system and write functions in the rotated system?

    Hey So, I was wondering how to convert from one coordinate axes to another... in particular, where the new axes are y = x and y = -x, as seen by the picture below I want it so that the Red dot in the new coordinate system will be (\sqrt2,0). Is there an easy way to do this? (My lookings on...
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    Series of sorts- Return 1 or 2 based on even or odd n

    So what you are saying is ... For input n = 1,2,3,4,5... a_n = 1,2,1,2,1,2There are a number of ways you can do this (click on Equations for Links )... 2- n mod(2) 2-[sin^2(\frac{\pi n}{2})]Just a couple that I thought off in my head... One is discrete, one is continuous
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    Trying to solve any equation ever with Recurrences

    So, just wanted to make some other interesting points (on the damping point i mentioned in the first post) So here's the equation x^2 -4x-9, with an input of 1. For the recurrence equation x = \frac{9+4x}{x}, here is the plot of number of recurrences (n = 1,2,3) and the value it produces...
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    Theory of Damping: General Equation?

    Is there a general equation of damping? I know that there is a second ODE for damping with regards to springs, and with RLC circuits, but is there a general form of damping equations (with critical-damp, overdamp, and under-damp). I know how to solve second ODEs, but I was wondering if there was...
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    What is the maximum rate of angle change for a function?

    So I have been thinking of this problem... what is the greatest rate of angle change for a function? As in, what is the point in which a function achieves its greatest rate of angle change... Well, the angle of a function can be determined by arctan(y') The Rate of Angle change is...
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    Sine Wave between two Functions

    Just Thought this would be cool to share with yall So say you have two functions, B(x) and A(x) The equation \frac{b(x)+a(x) + (b(x)-a(x))sin(nx)}{2} Will give you a sin wave in between these two functions (I was playing around with this and finally figured out the equation a while ago). N...
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    Is this function correct? (Not a homework Question)

    As long as you mean g(f(x)) and w(g(f(x))), then you have the right answer
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    Exploring Equality: A Fun Look at Mathematical Equivalencies

    Ʃ(1/2^k) from k = 1 to infinity
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    All possible ways to sum to a number

    Well here's something that might help (or not) I did something with interative sums (liek 4 + 5 + 6, or 12+13, or 23+24+25+26+27) that always differ by one (and only integers) So for 23, the only iterative sum is 11 + 12 For 26, its 5+6+7+8 Its basically related to the factors of the...
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    Trying to solve any equation ever with Recurrences

    So, I am trying to make up this theory of trying to solve any equation ever using recurrences... Ill show you what I mean Consider the quadratic function - f(x) = x^2 - 3x + 2 Well, obviously you could do this the easy way and do factoring and figure out x = 2 or 1... no big deal right? But...
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    What Methods Solve the Differential Equation f '(x) = 3 * f(x)?

    f'(x) = 3f(x) lets say y = f(x) for funsies y' = 3y (dy/dx) = 3y dy/(3y) = dx Integrate with respect to both sides... right side = X+ C Left side, , it equals (1/3)*(lny) (technically absolute value of y, but whatevs) so ln(y) = 3x + 3c ... which we can also say 3x + C, since C...
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