Recent content by glid02

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    Second order diff eq with two variables

    wow, yeah, that's all I had to do. Thanks a lot.
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    Second order diff eq with two variables

    I think the two different solutions have to be independent of each other - or not be multiples of each other. I'll give it a shot and see what happens though. Thanks.
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    Second order diff eq with two variables

    Here's the problem: x^2y''-3xy'-12y=0 with initial conditions y(1)=0 and y'(1)=7 I'm supposed to solve for y in the form y=c1y1+c2y2 y1 = x^6 by inspection Now to solve for y2 y2=y1v v can be solved for by the equation y1v''+(2y1'+py1)v'=0 where p is the function in front...
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    Second order diff eq with i

    Crap, nevermind, I left b^2 out of the quadratic formula, thanks anyways. Here's the question: Find y as a function of t from the diff eq: y''+6y'+25y=0 with the initial conditions y(0)=8 and y'(0)=8 I used the form r^2+6r+25=0 to solve for r and through the quadratic equation got r =...
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    Velocity and acceleration from a position equation

    yeah, I'm half retarded. I needed to make y a function of t and go from there. Thanks.
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    Solving Fluid Questions: 2 Spheres & U-Tube | 65 Characters

    For the first question you should draw a freebody diagram and from there you can get the net force acting on the sphere: buoyant force - weight. For the second question I think the circular diameter is best described by a donut, from the inside to the outside is 5.6 mm. The total weight of...
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    Velocity and acceleration from a position equation

    Here's the question: A particles position is defined by the equation x=y^2/6 and it moves at a constant velocity in the y-direction of 3 in/s. Find the velocity and acceleration when x=6 in. I know v=sqrt(vx^2+vy^2) and a is found the same way, but I have absolutely no idea how to find the...
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    Solution to 2nd order diff eq

    Never mind, I figured it out. Here's the question: Find the general solution to the homogeneous differential equation https://webwork.math.uga.edu/webwork2_files/tmp/equations/59/540a7a16e5c4e841a098d9d2a72f0a1.png The solution has the form...
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    Calculating Beam Deflection with Different Materials Using PL/AE

    Yeah, that helps. I'll give it a shot and you'll hear back from me if I still can't get the right answer. Thanks.
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    Calculating Beam Deflection with Different Materials Using PL/AE

    I'm supposed to find the deflection of a beam. It's steel with a brass shell, so they have different values for E. How do I do this problem using PL/AE. Intuitively I think I should take the average, but I have no idea if that's right or not. Thanks. I should probably give some more...
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    Solving the Logistic Model: Find P(66) with P(0)=3

    If I had I'd forgotten it. I should be able to solve from here (again). Thanks again for helping.
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    Solving the Logistic Model: Find P(66) with P(0)=3

    You lost me with the collecting. Can you give me another example?
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    Solving the Logistic Model: Find P(66) with P(0)=3

    OK I lied, I'm still not getting the right answer. dP/P(7-P)=6/700dt 1/7log(P)-1/7log(7-P)=6t/700+c log(P)-log(7-P)=6t/100+c Using e P-7+P=e^(6t/100)+c P=(e^(6t/100)+7)/2+c P(0)=3 so c=-1 Subbing 66 for t, I get 28.729 Still not right, what am I doing wrong now? Thanks again.
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    Solving the Logistic Model: Find P(66) with P(0)=3

    Yeah, I can solve that. Didn't think to separate variables for some retarded reason. Thanks for the help.
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    Solving the Logistic Model: Find P(66) with P(0)=3

    Here is the first question: A population P obeys the logistic model. It satisfies the equation https://webwork.math.uga.edu/webwork2_files/tmp/equations/11/02d0a645c053f1f6002d746c78143f1.png Assume that P(0)=3. Find P(66) First I multiplied both sides by dt and integrated, giving...
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