Recent content by sinClair

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    Prove limit of improper Integral is 1

    Are you thinking that you just keep on integrating by parts and then that will yield a sum that will be e? I'm having trouble summing up the uv part of the integration... I mean when i do it again I get -b^n*e^-b+e^-1+n(-e^-b*b^n-1+e^-1+integral...) this sums up...?
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    Prove limit of improper Integral is 1

    Homework Statement Show \mathop{\lim}\limits_{n \to \infty}(\frac{1}{n!}\int_{1}^{\infty}x^n\frac{1}{e^x} dx )=1 Homework Equations The hint is that e=\mathop{\lim}\limits_{n \to \infty}\sum_{k=0}^{n}1/k! The Attempt at a Solution First I wrote out the improper integral as limit...
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    Mastering Definite Integrals for Solving Tricky Problems

    Thank you so much. I was getting confused with changing the limits of integration back and forth but got it now, thanks.
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    Mastering Definite Integrals for Solving Tricky Problems

    Homework Statement Integrate \int_{0}^{1}\sqrt{\frac{4x^2-4x+1}{x^2-x+3}}dxHomework EquationsThe Attempt at a Solution U sub: let u=x^2-x+3 Then du=2x-1 and then have to evaluate \int_{3}^{3}\sqrt{\frac{du^2}{u}}dx But how with these limits of integration should this be 0? Not sure how to...
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    What is the Limit of an Integral Using the Definition of Riemann Sum?

    Thanks for the suggestion Tinker. Yes that is a convenient case but that also involves using the fundamental theorem of calculus to actually integrate. But for an arbitrary function it's impossible to explicitly calculate the integral like that and get a nice expression to take the limit. So...
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    What is the Limit of an Integral Using the Definition of Riemann Sum?

    Never mind, got it.
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    How can I overcome the frustration of missing a homework deadline?

    Yeah I really should not have pushed the assignment back. But it was a busy week, and I thought I could make it. Had I woke up on time, I would be comfortably done with my major obligations for the week. So part of the frustration was having these high expectations crushed. I feel like...
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    How can I overcome the frustration of missing a homework deadline?

    So I was finishing a problem set early this morning and felt great after I was able to complete it because I had been putting a lot of work into it. I decided to take a short nap before class. But I somehow fell into a deep sleep, and I didn't wake up when my alarm sounded. As a result, I...
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    Taylor's Formula in Higher Dimension/Higher order Total differentials

    Can someone post a link to evaluating higher order total differentials or show how to do it?
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    Taylor's Formula in Higher Dimension/Higher order Total differentials

    Thanks Ivy I got the first part, though I'm not exactly sure how that relates to taylor's theorem. I couldn't see what you wrote for the second quote--mind repeating what you said?
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    Taylor's Formula in Higher Dimension/Higher order Total differentials

    Homework Statement First write f(x,y) = x^2 + xy + y^2 in terms of powers of (x+1) and (y-1) Then write the taylor's formula for f(x,y) a = (1,4) and p=3 Homework Equations We write taylor's formula as: f(x) = f(a) + sum[(1/k!)*D^(k)f(a;h)] + (1/p!)D^(p)f(c;h) where sum is from k=1 to p-1 and...
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    Proving Limit of (-2xy)/sqrt(x^2+y^2) at (0,0)

    So it turns out I was responsible for some bad arithmetic and got the limit expression wrong. I was really worried when you replied, Ivy! The actual limit is (-2xy^2)/(x^2+y^2)^(3/2) as (x,y)->(0,0). Thanks for the response Ivy. I was not aware of that method of handling limits. But...
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    Proving Limit of (-2xy)/sqrt(x^2+y^2) at (0,0)

    Agh, I actually posted the wrong limit. I actually meant (-2xy^2)/sqrt(x^2+y^2).
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    Proving Limit of (-2xy)/sqrt(x^2+y^2) at (0,0)

    Homework Statement For a problem I came down to having to show that the limit of (-2xy)/sqrt(x^2+y^2) does not exist as (x,y)->(0,0) Homework Equations The Attempt at a Solution I tried taking iterated limits and showing they are not equal but I still get 0. I also tried...
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