Recent content by popo902

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    Solving Laplace Transform Homework: Equations 1 & 2

    yeh i saw that after about 30 minutes of just staring at the problem haha however, when you do carry j's into your laplace and get the inverse, they will still be complex right? so technically you could have a laplace shifted by a complex value using the e^at rule, where a = some j? thank you...
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    Solving Laplace Transform Homework: Equations 1 & 2

    I see i see but how did you get the equations to look like that? and could you get the inverse laplace transforms with complex numbers??
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    Solving Laplace Transform Homework: Equations 1 & 2

    Homework Statement Im having trouble finding ways to manipulate equations to fit something from the table The two I'm stuck on are these 1. \frac{1}{s^{2}- 2s + 3} (\frac{1+(s^{2}+1)e^{-3\Pi S}}{(s^{2}+1)}) = Y(s) 2.\frac{1}{s^{2}- 2s + 2} (\frac{s}{s^{2}+1} + s - 2) = Y(s)...
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    Rewriting Legendre's Equation for Orthogonality

    i can't believe i didn't see that haha thank you once again
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    Rewriting Legendre's Equation for Orthogonality

    Homework Statement i was reading on orthogonality of Legenedre's polynomials and this equation came up http://www.hit.ac.il/ac/files/shk_b/Differential.Equations/Orthogonality_of_Legendre_polynomials_files/img39.gif It's a rewritten form of Legendre's equation, but i can't see how to...
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    How to Prove Series Solutions for Differential Equations?

    oh i see now just some simplification of the series combination and it does cancel Thank you
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    How to Prove Series Solutions for Differential Equations?

    Homework Statement I was wondering, how you would prove that the solutions work for an equation? i know for a normal Diff eq, you just plug your solutions back into the equation but how would i go about showing that a series solution IS a solution to a problem? For instance, if they...
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    Finding the Function Represented by a Power Series

    i noticed from the first equation that the left sum, was the deriv. of the right, ecxept that the 2 was in front so technically it would look like this : y' + 2y = 0, when y = \sum_{n=0}^{\infty}{a_{n}x^{n}} = 0 so are you saying i should just solve the normal DE and i'll get the solution...
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    Finding the Function Represented by a Power Series

    Homework Statement Determine the an so that the equation \sum_{n=1}^{\infty}{na_{n}x^{n-1}} + 2\sum_{n=0}^{\infty}{a_{n}x^{n}} = 0 is satisfied. Try to identify the function represented by the series \sum_{n=0}^{\infty}{a_{n}x^{n}} = 0 Homework Equations The Attempt...
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    Engineering First order circuits, Inductors

    Homework Statement A security alarm for an office building door is modeled by the circuit [below]. The switch represents the door interlock, and v is the alarm indicator voltage. Find v(t) for t>0 for the circuit [below]. The switch has been closed for a long time at t=0-...
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    Supposedly simple differential equation

    Homework Statement Find the solution of dy/dt = 1/ (e^y -t), y(1) = 0 Homework Equations The Attempt at a Solution i tried separating the equation, but the subtraction gets in the way well this is what i have y = t - 1 + C/e^t i solved for t then i put that into the single...
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    Exploring the AC Generator in an LRC Circuit

    oh i see now, i solve for omega using that given equation thank you so much!
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    Exploring the AC Generator in an LRC Circuit

    ok for part b) Ipeak = Vpeak/ Z but don't i need the value of frequency to calculate this? because since the reactance of L anc C need the value, i need it here... or can i assume that it's at resonance? Then Z= R :S C) I read some more and i remembered that i could find the...
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    Inelastic Collision from different but not opposite directions. HELP

    keep in mind that the velocities of each skater are on different axes like ben.tien said, use that equation M1V1 + M2V2 = (M1 +M2)V and add the velocities as vectors in components. That should get you on the right path
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    Exploring the AC Generator in an LRC Circuit

    Homework Statement An AC generator in an LRC circuit produces a voltage V(t) = 1.414sin(wt) = 1.414sin(1000t) The values of inductance, capacitance, and resistance are shown in the diagram. Recall the w = 2pi*f. i made a picture of the diagram...
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