Recent content by danielatha4

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    What is the difference between momentum and kinetic energy?

    "mv = d/dt (1/2 mv^2)" Do you mean... mv = d/dv (1/2 mv^2) ?? wouldn't d/dt (1/2 mv^2) = mv(dv/dt) ?
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    Integrating ln(x) by parts: where does the x come from?

    n integrations of ln(x): x^n[ln(x)-(1/n!)(S)] where S is the sigma sum of 1/k where k=1 to n
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    Can ln(u)=u Be Solved for x Algebraically?

    Homework Statement Can this equation be solved for x? This isn't any type of homework. I'm doing this for fun. This equation came from an integration while solving a differential equation.
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    Calculating Length Along ln(x) Using Trig Substitution

    Yeah, looks right to me. Thanks for the help.
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    Calculating Length Along ln(x) Using Trig Substitution

    I did manage to get this far int/ sec^2A cscA = int/ (tan^2A + 1) cscA = int/ tanAsecA + int/ cscA = secA + int/ cscA is this right? isn't the integral of cscA equal to ln| tan x/2 | ?
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    Calculating Length Along ln(x) Using Trig Substitution

    Oh ok, I see that now. Thanks. I'll try a different way of solving this problem.
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    Calculating Length Along ln(x) Using Trig Substitution

    d/dA cscA = -cotAcscA so dcscA = -cotAcscA dA d cscA/-cotA = cscA dA cscA/cotA = secA -dsecA = cscA dA Which step is wrong?
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    Calculating Length Along ln(x) Using Trig Substitution

    I'm currently trying to find the length along function of ln(x) for the heck of it. I set up this integral for length L= int/ sqrt(1+(y')^2) so y'=1/x so the integral becomes int/ sqrt(1+(1/x^2)) = int/ sqrt(x^2+1)/x So I used trig substitution. I set tanA=x...
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    Derivative of x^x from first principles and discrepancy with calculators

    Actually if you set it up as ln(y) = x ln(x) You would only have to prove the derivative of ln(x), product rule, and implicit differentiation. You can prove d/dx ln(x) by setting up e^(lnx)=x and using implicit differentiation, and the derivative of e^x which is easily done with the...
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    Derivative of x^x from first principles and discrepancy with calculators

    Homework Statement I've been challenging myself with finding tricky derivatives lately, and I'm stuck with this one. Does anyone have a good way to differentiate x^x? I tried the difference quotient and you used the concept of pascal's triangle to try to simplify terms such as (x+h)^(x+h) or...
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    Proving the derivative of ln(x)What is the derivative of ln(x)?

    Thanks everyone, it makes a lot of sense using simpler methods on easier examples such as e^y=x or e^(lnx)=x lim x-> 0 (1+x)^(1/x) and lim x-> infinity (1+[1/x])^x both being equal to e is still a bit mysterious to me. What does this have to do with? Sequences and series possibly?
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    Proving the derivative of ln(x)What is the derivative of ln(x)?

    Homework Statement I'm trying to prove that d ln(x) / dx = 1/x This isn't a homework problem of mine for any class. I'm just doing it for fun, so if I'm faced with something I'm not sure of, I apologize. I've only made it through Calculus 2 The Attempt at a Solution Difference quotient...
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    Is 0.541r a Simple Fraction or Radian Measure?

    .aaaaaaaaaaaa ... = a/9 .abababababab ... = ab/99 (ab is not multiplication, simply the digits) .abcabcabcabcabc ... = abc/999 (again, not multiplication between a b and c) and so on
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    Undergrad MythBusters' flawed pendulum setup for collision impact testing

    Right! 41 from the bottom, 49 from the top. Touche Mythbusters. I'm just glad they didn't just put it at 45 like I initially thought they did.