Recent content by vm310

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    Inception [SPOILER ALERT]- What are your theories?

    I just saw this film and I thought it was amazing. Just going to list off some thoughts and observations: - so the military created "dream-sharing" for military training? - i don't understand how the notion of the totem works in the dream. how can you bring a physical object with you in a...
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    Cracking the Tough Integral: \int_0^1 \frac{ln(x+1)}{x^2+1}?

    I'm sorry but I can't find this integral identity anywhere, not in my book or online. Is this the standard form for the identity or has this a manipulation of one? Thanks so much
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    Cracking the Tough Integral: \int_0^1 \frac{ln(x+1)}{x^2+1}?

    Sorry to bring up this old post, but I was wondering how you decided to use this substitution? Thanks
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    Integrating ln(x+1)/(x^2+1) from 0 to 1: Need Help!

    Thanks Bohrok that link helped a lot. :D
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    Integrating ln(x+1)/(x^2+1) from 0 to 1: Need Help!

    here's what I've got so far: u=ln(x+1) du=\frac{dx}{(x+1)} dv=\frac{dx}{x^2+1} v=arctan(x) using integration by parts i got: arctan(x)ln(x+1)-\int\frac{arctan(x)dx}{(x+1)} than using integration by parts again i got: u=arctan(x) du=\frac{dx}{1+x^2} dv=\frac{dx}{x+1}...
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    Integrating ln(x+1)/(x^2+1) from 0 to 1: Need Help!

    yeah 100%. It's suppose to be a bonus question with some sort of prize if we can work it out on paper. The problem was copied correctly on the original post, i just forgot to put a dx at the end. when i plug the equation into my calculator i get 0.272198.
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    Integrating ln(x+1)/(x^2+1) from 0 to 1: Need Help!

    Thanks for the help guys but I'm still stuck on this problem. I tried inputting it into wolfram online integrator and it didn't really help. I also tried by parts with the u set to what was recommended above.
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    Integrating ln(x+1)/(x^2+1) from 0 to 1: Need Help!

    \int\frac{ln(x+1)}{x^{2}+1} The limits of integration are from 0 to 1. I've tried all the ways I've learned how to approach an integral so far and am stuck. (tried u-sub and by parts.) If anyone could throw me a bone that'd be great. Thanks!
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    Calculate Moment of Inertia - Stick and Ball

    Homework Statement What is the moment of inertia about the y-axis for the system as shown. The stick has a length of 2L and a mass of M. The solid sphere has a diameter of L and a mass of 2M. Homework Equations I=\intr2dm \lambda=\frac{m}{l} The Attempt at a Solution Should...
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    Angular Velocity Problem - Merry Go Round

    Thanks cepheid I got it!
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    Angular Velocity Problem - Merry Go Round

    Thank you for the quick response. I know that, L=I\omega and that, L=mvr I know I'm supposed to sum the masses of everyone who jumps on, but am I suppose to sum the radius also?
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    Angular Velocity Problem - Merry Go Round

    A 4.8m diameter merry-go-round is rotating freely with an angular velocity of 0.8rad/s. Its total moment of inertia is 1950(kg)(m2). Skid, Mitch, Larry, and Greezy all jump on at the same time. They each have a mass of 65kg.What is the angular velocity now? Relevant equations...
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    Angular velocity of a machine problem

    aright i got it thanks! i used: \omega=\omega0+\alphat and \theta=\theta0+\omega0+\frac{1}{2}\alphat2
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    Angular velocity of a machine problem

    A machine rotates at an angular velocity of 1.6rad/s. Its velocity is then increased to 6.2rad/s at an angular acceleration of 0.7rad/s2. (a) How many revolutions does it make during its acceleration? (b) How long does the acceleration take? Sorry I'm not quite sure as how to approach this...