Recent content by andrewjohnsc

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    What is the issue with u-Substitution in Integrating tan x sec^4 x dx?

    Thanks a lot!
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    What is the issue with u-Substitution in Integrating tan x sec^4 x dx?

    Homework Statement \inttan x sec^{}4 x dxHomework Equations U-SubThe Attempt at a Solution I did this two different ways and go two different answers. The correct way is \intsec^3(x)*sec(x)*tan(x) dx letting u= sec(x) and du= sec(x)*tan(x) = \int u^3 du = sec^4(x)/4 + C Which is good, but I...
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    Max/Min of a function using Lagrange Multipliers

    I don't understand how that constrains the function to 0<=x<=2pi 0<=y<=2pi
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    Max/Min of a function using Lagrange Multipliers

    Homework Statement Find the absolute maximum and minimum values for f(x,y) = sin x + cos y on the rectangle R defined by 0<=x<=2pi and 0<=y<=2pi using the method of Lagrange Multipliers. The Attempt at a Solution I don't know where to start in getting the constraint into something I...
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    Magnetic field of a finite-length wire

    In short your assumption that a finite wire's B field has cylindrical symmetry is not correct--the effects of the ends make the field lines shaped oddly and not in a way Ampere's Law can work for us.
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    Magnetic field of a finite-length wire

    Ampere's Law is only useful in calculating B for situations with very high symmetry. When calculating B of an infinite wire using Ampere's law we choose our path to be a circle around the wire so that B will always be tangent to our path. If the length of the wire isn't large compared to the...
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    Calculate the time constant (RC circuit)

    I'm doing the same problem--how did you get that expression for Rtotal?