# Calculus

- Elementary functions. Calculating limits, derivatives and integrals. Optimization problems
 Meta Thread / Thread Starter Last Post Replies Views Please post any and all homework or other textbook-style problems in one of the Homework & Coursework Questions... Feb23-13 09:24 AM micromass 1 39,999 Accidentally I wrote in the wolfram f(x) = f(1/x) the the wolfram give me the solution for this equation (f(x) =... T 01:09 PM HallsofIvy 2 120 Hi I am currently reading a book where this showed up: The author gave a ##3## parameter equation (note ##Y##... T 12:20 AM Red_CCF 1 272 i'm trying to integrate this: $$W=\frac{ε}{2}\int{\vec{∇}\cdot\vec{E})Vdτ}$$ where ε is a constant, E= -∇V, τ is... Y 09:35 PM Simon Bridge 4 164 I am working on the derivation of the angular momentum squared operator (in quantum mech.) and there is one step that... Y 07:53 PM hideelo 2 70 \int \frac{d}{dx}f(x)dx = f(x) + C_x \iint \frac{d^2}{dx^2}f(x)dx^2 = f(x) + xC_x + C_{xx} \int... Y 02:48 PM Mark44 7 216 Hey guys, I'm really really confused on how we come about the plane z = x - y. I always have been and it's proving to... Y 08:47 AM HallsofIvy 2 106 Hello, I've come across equations where people use the approximation \int_0^1 \exp(f(x))\, dx \approx \exp \left(... Y 05:17 AM Irid 0 71 I'm brushing up on calculus. I don't see how this derivative works. x(t) = A cos(ωt - \varphi) v(t) = dx / dt = ... Apr14-14 06:49 PM jbunniii 1 112 I understand how to use it, but I'm just getting really confused on when you use it? Is there a way you can look at... Apr14-14 06:45 PM Jhenrique 4 210 Hi! I am having trouble following the derivation from Euler's Equation to Bernoulli's Equation. The trouble lies in... Apr14-14 01:38 PM Einj 3 191 how do I find the derivative of tanh^-1(sinh(2x)) do I just find derivative of tanh^-1(x) this then substitute... Apr13-14 08:14 PM AMenendez 2 178 please tell me if i did this correctly: task: i'm trying to divide the differential dA by dV where.. dA =... Apr13-14 03:57 PM HallsofIvy 3 147 Hi all ! I'm new here :) So I'm facing some confusions here regarding integration by parts. While surfing through... Apr13-14 01:10 AM O.CModderz 9 318 the coordinates of cycloide are ##x= a (\theta- sin \theta)## ##y= a(cos \theta -1)## If i use ##\theta =\omega... Apr12-14 10:16 PM Simon Bridge 3 176 How is this limit evaluated? \lim_{k->0}\frac{sin(\pi k)}{sin(\frac{\pi k}{N})} I know that it is N, but I... Apr12-14 09:04 PM Jyan 0 149 A uniformly convergent sequence of continuous functions converges to a continuous function. I have no problem with... Apr11-14 01:26 AM GenePeer 5 494 Hello. My first time posting here. So... My question is kinda hard to explain but I will try to. So we all know about... Apr9-14 02:00 PM AlfredB 0 173 Hello, Consider two particles which interact via a Gaussian potential: V(\mathbf{x}) = \exp(-\mathbf{x}^2) I... Apr9-14 11:08 AM Irid 0 143 Hi, I'm doing this integration: I = ∫^{1}_{-1}1/(\pi√1-x2)dx I made the substitution x = cosθ, and I'm fine... Apr8-14 11:03 AM jbunniii 1 219 I'm not sure which category this post actually belongs to, or if the title of this post is even accurate. I guessed... Apr8-14 03:37 AM micromass 19 658 So this is a theoretical question I am not sure about with partial derivatives. Say we have function x(i,j) with ... Apr8-14 01:33 AM chicago77 2 230 hey pf! i have a few question about the physical intuition for divergence, gradient, and curl. before asking, i'll... Apr7-14 11:35 PM joshmccraney 8 312 Is it necessary for some point ##x## of the function to be saddle that ##f'(x)=0##? Apr7-14 04:34 PM Mark44 3 207 I'm looking for a way to write down an analytic approximation for the following integral: \int_0^\infty \frac{k... Apr7-14 03:04 PM csmallw 2 247 Hello all, I have the following integration: \int_{-\infty}^{\infty}e^{-j2\pi... Apr7-14 02:23 PM S_David 3 275 Function ##f(x)=x^4## has minimum at ##x=0##. ## f'(x)=4x^3## ##f'(0)=0## ##f''(x)=12x^2## ##f''(0)=0##... Apr7-14 10:08 AM HallsofIvy 2 204 I have been trying to follow how the complex Fourier coefficients are obtained; the reference I am using is at... Apr6-14 05:08 PM jellicorse 4 228 Hi guys, so I'm trying to create this thing that gets accelerometer values and integrate those values at about 25... Apr6-14 03:17 PM mathman 1 262 I saw in a question related to Signals and systems that the limits were taken from 5- to 10+ where the signs were in... Apr5-14 08:45 PM Mark44 5 253 Suppose ##f^{\prime\prime}## is continuous on an open interval that contains x = c 1. If ##f^{\prime}(c)=0## and... Apr5-14 11:27 AM 22990atinesh 3 236 I have a question about optimization. When we apply subgradient method to a differential optimization problem, will it... Apr5-14 10:53 AM peterlam 0 188 The popular fundamental theorem of calculus states that \int_{x_0}^{x_1} \frac{df}{dx}(x)dx = f(x_1)-f(x_0) But I... Apr5-14 04:51 AM Jhenrique 8 370 hey pf! i had a question. namely, in the continuity equation we see that \frac{\partial}{\partial t}\iiint_V \rho... Apr4-14 07:14 PM joshmccraney 2 236 I found this identity in the wiki https://upload.wikimedia.org/math/3/3/8/3381de258dc7b9d8733d05011c9811eb.png... Apr4-14 07:09 PM Jhenrique 0 197 I'm having a little bit of trouble understanding the equation of a cone.. It is given by (x^2)/(a^2) + (y^2)/(b^2)... Apr4-14 05:05 PM gopher_p 1 212 Hi! :smile: I have the following integral \int^{∞}_{∞} \frac{\delta^{n}}{\delta a}f(a,b,c)da there is any... Apr4-14 03:37 PM mathman 1 268 Dear All, I am unable to understand a simple mathematics relation. I spent 2-3 hours to Google multi-variable... Apr4-14 03:34 PM mathman 1 258 The graph of a differentiable function y=f(x) is 1. concave up on an interval I if f' is increasing on I. 2.... Apr4-14 11:06 AM 22990atinesh 9 356 Like we have the total differential of a function: http://s18.postimg.org/oj87l7x5l/imagem.png I was thinking, why... Apr4-14 10:44 AM Mark44 5 358 While watching a recent Youtube video on Marxian crisis theory and the Tendency Of The Rate Of Profit To Fall, I... Apr3-14 04:11 AM willem2 2 299