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  1. B

    Conceptual question on heat transfer (Steady-state)

    Ah that makes a lot of sense. Quick question though, is the heat flux equivalent to the J in electric flux as well?
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    Conceptual question on heat transfer (Steady-state)

    So this isn't a homework problem persay, it was given information but I just couldn't wrap my head on why this was true. We have 1-d heat transfer through a planar slab. If we have a T_a for the temperature outside, then as we T_1 for the temperature on one end of the surface, and T_2 for the...
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    Setting up a particular equation with (cos(x))^2

    Ah ok, I don't even need the general solution, just the particular solution, so should I just consider the two particular solutions of Asin(2x)+Bcos(2x) and y=1/4 (Solving the constants A and B?)
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    Setting up a particular equation with (cos(x))^2

    so (cos(x)^2) is ((1+cos (2x))/2. Which is 1/2 + cos(2x)/2. Am I missing something to get it into a degree one term and a trig function? For that I get A+ B*cos(2x)+C*sin(2x)?
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    Setting up a particular equation with (cos(x))^2

    Homework Statement Find a particular solution yp of the differential equation 2y''+9y'+2y=(cos(x))^2 Homework Equations The Attempt at a Solution I'm not really sure where to start? I solve for the homogeneous solution and get C1e^ -4.26556+C2e^-.2344355629=0. I'm just not sure where to...
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    Undetermined Coefficients

    oh ****.. yeah it's 25y.. but how does it change my particular solution? O.o
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    Undetermined Coefficients

    Yeah sorry, I was missing the first half of the question, if it says setup but don't solve for the coefficients for just the particular solution, is what I have correct because it keeps saying i'm wrong and I have no idea. Am I missing some steps?
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    Undetermined Coefficients

    Homework Statement Set up but do not solve for the appropriate particular solution yp for the differential equation y''+25y=2xsin(5x) using the Method of Undetermined Coefficients (primes indicate derivatives with respect to x). Homework Equations The Attempt at a Solution I first solved...
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    Problem with general solution to a complex roots diffy Q

    Ok so apparently it accepted e^(-x/2) but not e^(-.5x). Thank you so much for your help!
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    Question in complex general equation (2nd order)

    umm yeah thanks so much. -.5x apparently doesn't equal -x/2 anymore. Math as we know it has changed!
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    Problem with general solution to a complex roots diffy Q

    Eh it's online homework and it says "answer is incorrect" -.-" I entered: e^(-.5x)(a*cos(sqrt(3)*x/2)+bsin(sqrt(3)*x/2)) and my previewed answer was in the correct format too
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    Problem with general solution to a complex roots diffy Q

    Nope, it's given as a homogeneous equation (set equal to 0). Unless you're saying there's something i'm missing? The full equation is y=e^(-.5x)(a*cos(*x/2)+bsin(*x/2))
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    Problem with general solution to a complex roots diffy Q

    Homework Statement Question: I'm confused about how to app Find the real-valued general solution of the differential equation y''+1y'+1y=0 where primes indicate differentiation with respect to x. (Use the parameters a, b, etc., for undetermined constants in your solution.) The...
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    Question in complex general equation (2nd order)

    Question: Find the real-valued general solution of the differential equation y''+1y'+1y=0 where primes indicate differentiation with respect to x. (Use the parameters a, b, etc., for undetermined constants in your solution.) My attempt: Use characteristic equation: r^2+r+1=0 I used the...
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    Line Integrals of piecewise curves to find mass of wire

    Homework Statement A wire lies along the piecewise linear curve extending from the point (4,3) to the point (6,15) to the point (12,15). If the density of the wire is given by (xy)=3xy+2y, use a line integral to find the mass of the wire. Homework Equations The Attempt at a Solution...
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    Triple integrating cylindrical coordinates?

    i have the same problem and I can't seem to get the right answer .. i'm entering the answer in so it doesn't really matter if it's simplified or not
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    Triple integral with an image given

    ok i changed the theta and got 346.. but the answer is still wrong =[
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    Triple integral with an image given

    Homework Statement Integrate the function f(xyz)=−4x+6y over the solid given by the figure below, if P = (5,1,0) and Q = (-5,1,5). where P=(5,1,0) and Q=(-5,1,5) Homework Equations r²=x²+y² tan theta=y/x z=z y=rsintheta x=rcostheta The Attempt at a Solution So I treated this...
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    Triple Integral problem (maybe using spherical coordiantes)

    Oh so you do suggest that I change the cone? altering it doesn't mess with the problem? i still can't seem to integrate this =[
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    Triple Integral problem (maybe using spherical coordiantes)

    Homework Statement Integrate the function f(xyz)=−4x+6y over the solid given by the "slice" of an ice-cream cone in the first octant bounded by the planes x=0 and y=x*sqrt(22/3) and contained in a sphere centered at the origin with radius 13 and a cone opening upwards from the origin with top...
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