Recent content by Apothem

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    B First Order Non-Linear ODE (what method to use?)

    Hi, The problem is to solve: dy/dx = −[2x + ln(y)]*(y/x) Attempt: I have tried to see if it is exact, I found it not to be, I can't easily find a function to multiply by to make it exact either (unless I am missing something obvious). It clearly isn't seperable, nor is it homogenous (I know...
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    Expressing a quadratic form in canonical form using Lagrange

    Problem: Express the quadratic form: q=x1x2+x1x3+x2x3 in canonical form using Lagrange's Method/Algorithm Attempt: Not really applicable in this case due to the nature of my question The answer is as follows: Using the change of variables: x1=y1+y2 x2=y1-y2 x3=y3 Indeed you get...
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    I Prove the sequence is exact: 0 → ker(f) → V → im(f) → 0

    Problem: Let f ∶ V → V be a linear operator on a finite-dimensional vector space V . Prove that the sequence 0 → ker(f) → V → im(f) → 0 is exact at each term. Attempt: If I call: a: 0 → ker(f), b: ker(f) → V, c: V → im(f), d: im(f) → 0. Then the sequence is exact at: ker(f) if...
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    I Interval of existence and uniqueness of a separable 1st ODE

    Problem: y'=((x-1)/(x^2))*(y^2) , y(1)=1 . Find solutions satisfying the initial condition, and determine the intervals where they exist and where they are unique. Attempt at solution: Let f(x,y)=((x-1)/(x^2))*(y^2), which is continuous near any (x0,y0) provided x0≠0 so a solution with y(x0)=y0...
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    Supporting a plank of wood with a mass at the centre

    No need for help anymore I have figured it out! Thanks anyway.
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    Supporting a plank of wood with a mass at the centre

    Could you give me a hint of how to approach the question please?
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    Supporting a plank of wood with a mass at the centre

    Sorry I have just looked over my notes and realized that I wrote: "two people are holding the plank at either end they move further apart", so it must mean they are just walking back". I'll edit it on the first post now
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    Supporting a plank of wood with a mass at the centre

    Maybe it is that then, as I said I probably misheard what the teacher said when I wrote the problem down.
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    Supporting a plank of wood with a mass at the centre

    It could well be possible I misunderstood the question the teacher asked, as we did have to write it down, if so I will ask next time I see him.
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    Supporting a plank of wood with a mass at the centre

    I think the teacher was just trying to use an analogy to make it easier to understand. I am just in the process of creating images, which I will upload in a second.
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    Supporting a plank of wood with a mass at the centre

    Homework Statement "Two people are holding a plank of wood at either end, with a mass located at the halfway point between them, they both walk backwards extending their arms, the mass still being halfway between them. The plank becomes harder to support, why is this?" Homework Equations Maybe...
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    How does length affect the bending of a horizontal beam?

    Homework Statement We were shown this image ^ We were later told that it is suggested that the depression (y), is directly proportional to the length of the beam cubed (L3). We were asked to give reasons why this is so. EDIT: The 1kg mass is placed at L/2 Homework Equations y is directly...
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    Simple Harmonic Motion Guitar String Question

    Sorry, I am unsure on what you mean. I understand your first point, just not about the midpoint.
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    Simple Harmonic Motion Guitar String Question

    Homework Statement Question: "The midpoint of a guitar string oscillates with an amplitude of 2.24mm with a frequency of 400Hz. Calculate: i) The maximum speed at this point ii) The maximum acceleration of the string at this point" Homework Equations Suitable formulas: x=Asin(2*pi*f*t) ...
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    Density and r.m.s of an ideal gas

    Sorry I have added it now.
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