Recent content by Airp

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    Minimum Period of Oscillation Disk

    Thank You!
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    Minimum Period of Oscillation Disk

    Homework Statement how far from the rim of a disk of Radius R must the pivot point be located in order for its period of oscillation to be a minmum where R is the distance from the point to the centre of mass? I'm stuck at the derivative because I saw a similar problem where the answer is...
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    Identification of a ratio using Refractive indices (RESOLVED)

    Oh, I actually found the solution... You have to add the X's which equal to one. With the system of equation you can substitute and only then you only have one unknown! (Is there a way to close the thread as it is not useful anymore :) )
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    Identification of a ratio using Refractive indices (RESOLVED)

    Homework Statement I need to find the X of two substances using only the data found in lab. Which is: nmixture=1.4156 nbutan-2-one=1.3787 ntoluene=1.4970 For the mixture, I don't know what X (the mole fraction) is. That is what I must find out. Homework Equations nmixture= (Xbutan-2-one...
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    Integrate x³√(x²+16) using trigonometric substitution

    Thank you! It works now, my mistake was simply that I forgot to take the sqrt of sec^2
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    Integrate x³√(x²+16) using trigonometric substitution

    I can officially say that it works now! Thank you Faris! Such a "minor" mistake that really changed everything in the problem!
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    Integrate x³√(x²+16) using trigonometric substitution

    Ok, I'm currently trying, correcting the mistake I made with my sec^2. It looks good!
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    Integrate x³√(x²+16) using trigonometric substitution

    Thank You Mark! I'm still learning to use Latex... I changed it and it should appear ok, now!
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    Integrate x³√(x²+16) using trigonometric substitution

    No problem! I tried using Latex, but it doesn't work...It's #6
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    Integrate x³√(x²+16) using trigonometric substitution

    I'm trying to find the integral of the equation, but it doesn't give the same answer as the one I'm supposed to get, and I don't know what I'm doing wrong. I'm using trigonometric substitution which let's x=4sinΘ.
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    Integrate x³√(x²+16) using trigonometric substitution

    Homework Statement Integral of $$ x^3\sqrt{x^2+16}dx $$ answer should give $$ 1/5(x^2+16)^{5/2} -16/3(x^2+16)^{1/2}+C $$ Homework Equations x=atanθ The Attempt at a Solution Mod note: The integral is ##\int x^3 \sqrt{x^2 + 16} dx## The published answer is ##1/5(x^2+16)^{5/2}...
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    Integration by parts for z³e^(z²)

    Whoa didn't know that thanks!
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    Integration by parts for z³e^(z²)

    This is what I finally did! Thank you again!
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    Integration by parts for z³e^(z²)

    Oh ok! I think I get now! Thank you to everybody on this thread for your help! I'll try that!
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    Integration by parts for z³e^(z²)

    Wel, normally you try going the other way around, but it still doesn't work as shown in the first picture...
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