Recent content by LostEngKid

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    Complex Analysis Qn: Show Constant Function in B(z0; r)

    Yes i think i do. Thanks for being patient with me and thanks for all the help, i never would have been able to answer this question on my own.
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    Complex Analysis Qn: Show Constant Function in B(z0; r)

    I know that the answer is supposed to be that it hasnt changed but I am not sure how to prove it. The derivative is the rate of change, and its 0 no matter where you take it, so the function isn't changing. I find it really hard to get my head around this topic, in the real plane the function...
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    Complex Analysis Qn: Show Constant Function in B(z0; r)

    Oh i see, for some reason i was thinking f(z) = x + iy So if we know that v(x,y)=0 and that the function is analytic then du/dx and du/dy have to equal 0 to satisfy CR. So if the derivative is 0 then the function has to be a constant?
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    Complex Analysis Qn: Show Constant Function in B(z0; r)

    Okay, so u(x,y) = x and v(x,y) = 0 That means du/dx = 1 and all the others = 0 which means that the function isn't differentiable, but the question says its analytic so it is? So obviously I've done something wrong... If v(x,y) = y then dv/dy =1 and it works. So I am assuming this is what I am...
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    Complex Analysis Qn: Show Constant Function in B(z0; r)

    You split the function into real and imaginary parts, u(x,y) and y(x,y) and then take the partial derivate of each with respect to x and y. If du/dx = dv/dy and dv/dx=-du/dy for (xo, yo) then the equation is differentiable at zo. And then the derivative is du/dx + i dv/y.
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    Complex Analysis Qn: Show Constant Function in B(z0; r)

    Thanks for replying winter85 Okay so i know that a function is analytic over a given open set if it is differentiable at every point in the set...thats about all I've picked up so far, the next thing that was covered in my lectures was the cauchy reimann equations which if i remember correctly...
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    Complex Analysis Qn: Show Constant Function in B(z0; r)

    Homework Statement Suppose z0 = x0 + iy0 2 C, and r > 0. Further, suppose that f(z) is a real valued function that is analytic on the open box B(z0; r) = { x + iy | x0 < x < x0 + r; y0 < y < y0 + r }. Then show that f(z) must, in fact, be constant on the box B(z0; r). The Attempt at...
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    Understanding Laplace Transforms: Solving Problems and Applying Properties

    oops yeah i did mean 1/(s+1) danago and Pere i wouldn't have a clue about sinh(t) and cosh(t) a exponentials, maybe i should have paid more attention in first year maths
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    Understanding Laplace Transforms: Solving Problems and Applying Properties

    Hi all, 2 questions here 1) I've been doing some questions on laplace transforms and have been running into some trouble getting my answers into the same form as the answers given with the questions. For example: f(t) = 1 - e^(-t) Using the linearity property i got 1/s - 1/(s-1) which is...
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    Voltage Regulator Project: Hysterisis, 9V, 15 Ohm Load

    hey guys, I've got to make a voltage regulator for a uni project. it has to use hysterisis and produce 9v out from a 16Vrms AC powerpack over a 15 ohm load. It also needs overload protection, I've drawn up the attached circuit, i think it will work and filled in some of the values i know but I...
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    Complex Integration: Evaluating Line Integrals on a Circle

    Thanks for the help guys i really appreciate it, i think ill definitely need this site to pass maths this semester, god i hope i don't have another maths subject next year Just on a side note, I am doing electrical engineering and I am wondering when complex analysis would be used in a...
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    Complex Integration: Evaluating Line Integrals on a Circle

    Evaluate the Line Integral (assume counterclockwise orientation) \oint _{|z| = 2 } z^n \bar{z}^m dz for all m, n \in Z I have no freaken clue about how to even attempt this...
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