Recent content by Econometricia

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    Laplace Transform of $\sqrt{\frac{t}{\pi}}\cos(8t)$

    L\{\sqrt{{t}/{\pi}}\} = \frac{1}{s^(3/2)} and L\{\cos(8t)\} = \frac{s}{s^2 + 8^2} So we are looking for ( 1 / (pi^(1/2)) \int (t-v)^(1/2) cos(8v) dv Integrating from O to t
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    Laplace Transform of $\sqrt{\frac{t}{\pi}}\cos(8t)$

    Yes, I do know those transforms. I am now trying to express the integral as a gamma function.
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    Laplace Transform of $\sqrt{\frac{t}{\pi}}\cos(8t)$

    1. find the Laplace transform of \sqrt{t/pi}cos(8t). 2. Tried to look at the tables and combine things but I'm not very sure where to start.
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    Differential Equations Inverse Laplace(Partial Fractions)

    1. L-1{(3s+2)/ (s2+2s +10)} After completing the square I get to 3s+2 /(s+1)2 + 32 which suggests two solutions or one. They decompose the fraction into [(A)s+1 /(s+1)2 + 32 ]+ [(B) 3/(s+1)2 + 32] I am unsure of how this decomposition works I thought that we would take A(3s) as the numerator...
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    Volume of Solids of Revolution

    Yes, not 2 equal halves but the rotation around the x=1 axis would cover the right hand side of the curve in rotation and double over so can't we ignore that piece?
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    Volume of Solids of Revolution

    Find the volume of the solid st, 1. y=cos x , y= 0 in [0,pi] ; Rotated around x=1 2. I am slightly confused, I see that the area will double around twice so I can just use the left half of the curve. I am just not sure how to do so.
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    Integration by partial fractions.

    361/365 41/365 36/365 It was on an old exam lol. I hope there's nothing like that on our exam =O.
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    Integration by partial fractions.

    Yeah... It must be some type of cruel joke.
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    Integration by partial fractions.

    Yes the first version is correct. -.- Do you have any suggestions?
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    Integration by partial fractions.

    a=37/41 b=5/41 c = 7/41 I mean its not that outrageous I guess. I guess I just assume I do things wrong lol.
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    Integration by partial fractions.

    Yes, I used a solver to check my work because it did not seem right. I am fairly sure the fractions are broken up properly as well. =(
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    Integration by partial fractions.

    1.\int2x^2+x+9/(9x+1)(x^2+9) dx 2. (A/9x+1) + [(Bx + C ) / (x^2 + 9)] I get the worst numbers when I solve the system. The question is from an old exam and calculators are not allowed. Am I doing something wrong or is there another way to integrate this?
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    Check Out This Incredible Math Trick

    Sorry if this has been posted. Thought it was cool! http://www.wimp.com/crazymath/
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    Solving Limits and Discontinuities: f(x)= 3x2-12x / x2-6x +8

    Ugh! Thanks I am just a fool and factored incorrectly. Final exams =(. Thank you ! 3x(x-4) / (x-4)(x-2) = f(x) So the lim as x-->4 f(x)=6
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    Solving Limits and Discontinuities: f(x)= 3x2-12x / x2-6x +8

    1. f(x)= 3x2-12x / x2-6x +8 f(x) can be made continuous at x =4 by defining f(4)=6 I know that the removable disc. is at x=2 and the non removable is at x=4. So there is an asymptote at x=4. How is it possible to define it there?
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