Recent content by andrew.c

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    How can I efficiently pass variables from an m-file to a function in MATLAB?

    Hiya, I have been trying for hours to figure out how to pass a variable from an m-file to a function, i could get it to work by making the variables global, but I've beeen told this is inefficient. Any ideas? Cheers!
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    2nd order non-homogeneneous ODE - how to find PI

    PI = Particular Integral :)
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    2nd order non-homogeneneous ODE - how to find PI

    I don't really understand what you mean by this.. However, the PI for sin3x is Acos3x + Bsin3x, i think... so if you have to multiply by x (don't really understand why?) then the PI would be x(Acos3x + Bsin3x)?
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    Partial Differentiation: How Do You Differentiate Arc Tangent Terms?

    Yeah, I just missed a bit of chain-rule didn't I? Thanks for the help :)
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    Solving ODE with Bernoulli's Method: y''+(y')2 = y

    Not worked through this, but using the substitution p = y', surely you would get: p'+p^2 = y and NOT p'p +p^2?
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    2nd order non-homogeneneous ODE - how to find PI

    Homework Statement Find the general and, if possible, particular solutions of the following ordinary differential equations: y''+9y=36sin3x (hint: modification rule for PI) Homework Equations Knowledge of ODE's y = y_{aux}+y_{particular} The Attempt at a Solution I get the compementary...
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    Partial Differentiation: How Do You Differentiate Arc Tangent Terms?

    I get that - if you could have a look at my attachment, that has the question in it :)
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    Partial Differentiation: How Do You Differentiate Arc Tangent Terms?

    I was working through this problem, I understand the method, but got stuck trying to differentiate the arc tan terms... In the table of standard derivatives, \frac{d}{dx} \arctan{x} = \frac{1}{1+x^2} and for PDE's, you treat y as constant when differentiating w.r.t. x --- Any...
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    Undergrad Integration by Parts guidelines

    Check out PatrickJMT on youtube, he explains it in a couple of videos.
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    Momentum Flux: Quick Question (Product Rule)

    Thanks That was easier than I thought!
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    Momentum Flux: Quick Question (Product Rule)

    Homework Statement Heya, I can expand the term on the LHs and get the term on the RHS no problem :) But, I don't understand how the bottom line is arrived at; I think its basically just a backward engineering of the product rule, but I can't get it! Any help would be useful
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    How Do These Algebraic Expressions Equate in an ODE Problem?

    Homework Statement I'm doing an ODE problem, and I have a set of solutions for it, but I do not understand how \frac{y+1}{y-1} = Cx^2 can equal y = \frac{1+Cx^2}{1-Cx^2} Many Thanks!
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    Calculating Friction in Pin Joints for Linkages | Homework Help

    Only in 1st year, but that logic sounds right based on my lecture notes
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    Calculating Moments and Resolving Forces in Engineering Statics

    Yes, should use 4.5, not 1.5. Thanks, I got the right answer!
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    Calculating Moments and Resolving Forces in Engineering Statics

    Homework Statement http://img512.imageshack.us/img512/2617/staticsquestion4.jpg Homework Equations - Ability to resolve forces into components - M = Fd The Attempt at a Solution (a) Resolve the force acting at an angle into components... 10kN force = -10cos50i - 10 sin 50 j...