Homework Statement
"Show that - \int^1_0 x^k\ln{x}\,dx = \frac{1}{(k+1)^2} ; k > -1.
Hint: rewrite as a gamma function.
Homework Equations
Well, I know that \Gamma \left( x \right) = \int\limits_0^\infty {t^{x - 1} e^{ - t} dt}.
The Attempt at a Solution
I've tried various substitutions...
Homework Statement
y' + (2/t)y = (cost)/(t^2), and the following condition is given: y(pi) = 0Homework Equations
The Attempt at a Solution
After employing the integrating factor, I find the solution to be:
y=e^{-2t} \int e^{2t} \frac{\cos(t)}{t^2} dt.
Evidently, this simplifies all the way to...
Homework Statement
I need to integrate dx/dt=k(a-x)(b-x) and then rearrange to find xThe Attempt at a Solution
1/((a-x)(b-x))dx = k dt
Integrating dx using partial fractions:
1/(b-a)×(ln((a-x)/(b-x))=kt+c
when t=0 x=0
∴c=(ln(a/b))/(b-a)
then when I rearrange I get...
I have a question regarding what I highlighted in the paint doc.
How can they assume that the function is increasing?
As a matter of fact its not increasing on the entire interval from 0 to pi.
Hello everyone,
What does it mean if I integrate Newton's law of universal gravitation with respect to r.
F= GMm/r^2 become 3GMm/r^3 . Is this the work needed to escape a gravitational pull ?
Thank you
Hi,
I'd like to numerically solve the IVP:
x^2 y y''+2x y y'+2 y^2+xy'-x^2 y^3-(x y')^2-y=0,\quad y(x_0)=1,y'(x_0)=0
around the unit circle, x=e^{it}. When I attempt to solve it around the entire circle, I think the integration is veering of course. I believe the solution is single-valued...
Integrating a product of two functions - one "lags" the other
I am wondering if there is a way to integrate the following function without first expanding the brackets:
\int\limits_{x1}^{x2} x^2\left(x-a\right)^2\,dx
The idea behind the question is a bit more complex than I am letting on...
Homework Statement
A particle of mass m is confined to move in a one-dimensional and Diract delta-function attractive potential V(x)=-\frac{\hbar^2}{m}\alpha\delta(x) where \alpha is positive.
Integrate eh time-independent Schrodinger equation between -\epsilon and \epsilon. Let...
Homework Statement
Use the method of separation of variables or an integrating factor to find a particular solution of the differential equation that satisfies the given initial condition.
y'=x-y+2 ; y(0)=4
2. The attempt at a solution
I've used an integrating factor of e^{x} to...
So the problem is ∫(6x+5)/(2x+1)dx. I know the proper way to solve this is to long divide these two expressions and then solve. However, I tried doing it with substitution.
u = 2x+1
dx = du/2
I then reasoned that 3u + 2 = 6x+5 since 3(2x+1) + 2 = 6x+3+2 = 6x+5 so I substituted it on top...
Here is the question:
Here is a link to the question:
Show that the given equation is not exact and find the right integrating factor to make this equation exact? - Yahoo! Answers
I have posted a link there to this topic so the OP can find my response.
I'm trying to figure out the general solution to the integral ##\int \frac{d^ny}{dx^n} \, dy##, where n is a positive integer (Meaning no fractional calculus. Keeping things simple.).
So far, I have been working with individual cases to see if I can establish a general pattern and then try a...
Homework Statement
Integrate -π∫π H(t-π/2)*sin(2t)dt
Homework Equations
See above.
The Attempt at a Solution
I can rationalize the slightly simpler integral for the same limits of H(t)*sin(2t) as coming out to 0 due to the definition of the unit step function, but I'm wondering...
Here is the question:
Here is a link to the question:
Differential equations math question? - Yahoo! Answers
I have posted a link there to this topic so the OP can find my response.
Homework Statement
\int^{1}_{0}\int^{e^x}_{e^-x}\frac{lny}{y}dydx
The attempt at a solution
So I am integrating ln(y)/y and I tried it by parts, first with u = ln(y), dv = 1/y, and therefore du = 1/y, and v = ln y
but if I use that I get
(ln(y))2-\int\frac{lny}{y} again.
So I tried...
This is actually related to a post I made earlier in the differential equations forums, but I've since realized that solving the equations themselves is not necessarily the best way to get where I want to go. Perhaps it's better suited to this forum, since it is an integration problem that I...
I've been trying to figure out how to integrate 1/(x+ln(x)) but am not getting anywhere. Mathematica can't do it, and I haven't found it in lists of integrals.
Does anyone know if this integral exists in closed form?
Same goes for (x+ln(x))/(1+x+ln(x))
Thanks!
zeroseven
Homework Statement
We define I_{n} = \int_{-∞}^{∞}x^{2n}e^{-bx^{2}}dx, where n is a positive integer. Use integration by parts to derive:I_{n}=\frac{2n-1}{2b}I_{n-1}
Homework Equations
Parts formula.
The Attempt at a Solution
So I'm just stuck here, I'm baffled and confused. Firstly if I...
Homework Statement
I am trying to integrate the PLanck function to get the Stefan Boltzmann law. After factoring out constants, and substituting x = hv/kT I am left with the following integral:
B(T) = ∫ x3/(ex - 1) dx integrated from 0 to ∞
The next step in my notes is that the result...
Homework Statement
Hi I have a question about integrating to find the volume of a sphere but before that i need to tell all other results i got or it will not make sence.
1. I needed to show how you get the formula for finding the volume of a sphere by the help of a cirkle with radius r . I...
Homework Statement
http://img801.imageshack.us/img801/4227/capturebsw.png
Homework Equations
The Attempt at a Solution
Alright I'm not really sure how to solve this problem. I have redrawn the circuit below without the operational amplifier. In ideal operation amplifiers there's no...
In my diffraction notes, this integral comes up on the page about Babinet's principle:
\int ^{y=\infty}_{y=-\infty} \int ^{x=\infty}_{x=-\infty} exp(-i(px+qy)) dx dy = \delta (p,q)
I'm not sure how this integral is derived as carrying out the integration and putting in the limits seems to...
This is (perhaps) a tricky question regarding the moment of normal distribution.
Let f(x) be the pdf of normal distribution with mean (-σ^2/b) and variance σ^2, where b is just a constant. The goal is to solve the integral
∫ x^3 f(x) dx
integrating from 0 to ∞.
I am stuck. Any...
I've tried out the two body problem and tried to work out the trajectories with respect to their center of mass frame(located at the origin) as follows (it worked!:smile:):
particles = m1 and m2
Fm1 = force of m2 on m1
Fm2 = force of m1 on m2
a = Gm2\hat{r} / r2
\hat{r} is the unit vector...
Homework Statement
Apologies for the vague title, I'm not reall sure what I'm look at here! I am doing some revision on solving the Friedmann equations, and in a lot of cases I end up having to integrate a function that looks like
(xan - 1)-1/2 da = dt
where a is a function of t, x is a...
Homework Statement
Find the integral of
This was the question. There is a way to do it by long division but I am confused with Long division. Instead I tried to do by the method below but I failed...
Homework Equations
NoneThe Attempt at a Solution
I thought maybe I could reduce the...
Homework Statement
∫arctan(√x)dx.
Using the substitution √x=t:
∫arctan(√x)dx = ∫arctan(t)dt2
This is what I've got written in a solution manual. I don't see why the dt would be squared. Could anyone care explaining me? thanks
Homework Statement
Consider the general linear homogeneous second order equation:
P(x)y'' + Q(x)y' + R(x)y = 0 (1)
We seek an integrating factor μ(x) such that, upon multiplying Eq. (1) by μ(x), we can write the resulting equation in the form
[μ(x)P(x)y']' + μ(x)R(x)y = 0...
Homework Statement
\Psi(x,t) = \int^{\infty}_{-\infty} C(p)\Psi_{p}(x,t) dp
is a solution to the Schroedinger equation for a free particle, where
\Psi_{p}(x,t) = Ae^{i(px-Ept)/\hbar}.
For the case C(p) = e^{-(p-p_{0})^{2}/\sigma}
where \sigma is a real constant, compute the wavefunction...
Homework Statement
This is an arc length problem in three dimensions. I was given the vector r(t)=<et, 1, t> from t=0 to t=1
Homework Equations
Arc Length= \int |\sqrt{r'(t)}| dt from t1 to t2
where |\sqrt{r'(t)}| is the magnitude of the derivative of the vector
The Attempt at a...
Homework Statement
Find the length of the curve between x=0 and x=1. Note: can this be done without a calculator?Homework Equations
y = sqrt(4-x^2)
The Attempt at a Solution
x=2sin∅
dx = 2cos∅ d∅ sqrt(4-4(sin∅)^2) ---> 2cos∅integral (0 to 1) sqrt(1+(-2sin∅)^2)
integral (0 to 1)...
Hello,
I'm having problem understanding the output of the integrating op amp.
https://www.dropbox.com/s/djpg0uhi465ot86/download2.png
https://www.dropbox.com/s/djpg0uhi465ot86/download2.png
https://www.dropbox.com/s/p9bp9tlyykhjtvf/download.png...
Am I integrating this right: (x^2 + 3x + 11)/(x+2)^4 ?
1. ∫(x2 + 3x + 4)/(x+2)4dx
2. With these sorts of problems, I think about integration by partial fractions.
So in this case, the denominator factors are all the same, so I have to make each one with different exponents.
I wrote...
when using the reimann integral over infinite sums, when is it justifiable to interchange the integral and the sum?
\int\displaystyle\sum_{i=1}^{\infty} f_i(x)dx=\displaystyle\sum_{i=1}^{\infty} \int f_i(x)dx
thanks ahead for the help!
Homework Statement
for the following integrals, am I allowed to break them up like so:
1. ∫(1)/(sqrt(16-9x²)³) dx
= ∫(1)/(√16)³ · ∫(1)/(√-9x²)³ dx
2. ∫(x²)/(sqrt(x²-9)) dx
= ∫(x²)/(√x²) · ∫(x²)/(√-9) dx
3. ∫(1)/(x²(sqrt(a²+x²))) dx
= ∫(1)/(x²) · ∫(1)/(√a²) · ∫(1)/(√x²) dx...
Homework Statement
Volume of the region bounded by 1/x^4, y = 0, x = 2, and x = 6 about the axis y = -4
Homework Equations
The Attempt at a Solution
The height for any shell is x(y) - 2, or \sqrt[4]{\frac{1}{y}} - 2
The radius of any shell is y + 4
So the circumference...
given a function f(x) that is piecewise smooth on interval -L<x<L except at N-1 points, is \int_{-L}^L f'(x)dx legal or would i have to \sum_{i=1}^N \int_{x_i}^{x_{i+1}} f'(x)dx
where x_{N+1}=L and x_{1}=-L
also, am i correct that if f(x) is piecewise smooth, then f'(x) is piecewise...
Homework Statement
Use parametrisation first, derive the equation including y and p = \frac{dy}{dx} and use the integrating factor method to reduce it to an exact equation. Leave the solution in implicit parametric form.
(y')^{3} + y^{2} = xyy'The Attempt at a Solution
I'm really lost at...
Here is the question:
Here is a link to the question:
Integrating Factor Help Please!? - Yahoo! Answers
I have posted a link there so the OP can find my response.
Homework Statement
Integrate the following:
Homework Equations
∫(x^2+x-7)/(x+3)
The Attempt at a Solution
The only way I can think of solving this would be to split up each term into a separate fraction.
Homework Statement
integrate the following:Homework Equations
∫(x/(x-1)^3The Attempt at a Solution
i've tried u-substitution, finding an inverse trig function that matched the formula, and still can't figure out how to solve this problem.
u-subtitution for u=x gives the same problem...
I am sure that this can be done, but I haven't been able to figure it out, Is there a way to integrate a differential form on a manifold without using the parametric equations of the manifold? So that you can just use the manifold's charts instead of parametric equations? If you a function...
Homework Statement
I am trying to integrate the function
\int _{-\infty }^{\infty }(t-1)\delta\left[\frac{2}{3}t-\frac{3}{2}\right]dt
Homework Equations
The Attempt at a Solution
I think the answer should be \frac{5}{4} because \frac{2}{3}t-\frac{3}{2}=0 when t=9/4. then (9/4-1) = 5/4...
I'm trying to integrate acceleration from an acceleraometer to find a distance travelled.
I have heard all the stories about this not being accurate but i didn't come up with the method I'm just trying to implement an algorithm to do it. I'ts justan estimate for wear rates, not positioning...
Hello-
I have a diffusion profile, in which I plot the decrease in concentration versus distance of my sample. I am trying to find the increase in mass of the overall sample. How would I do this?
I have integrated the function and am wondering what type of information that would supply...
The integral of 1/x is ln(x). Where does that come from? That always puzzled me. We can continue to take derivatives through x^0 and into the negative integers, and just use the plain old power rule to get the answers. We can do the same for the integral of x all the way from negative...
Hi all,
I'm trying to integrate the function below with respect to x
exp(ix)-exp(-ix)
With infinity and negative infinity as the limits. Would the integration be possible?