# Calculus

- Elementary functions. Calculating limits, derivatives and integrals. Optimization problems
 Meta Thread / Thread Starter Last Post Replies Views Views: 125,416 Announcement: Follow us on social media and spread the word about PF! Jan16-12 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 45,442 This is going to be a really dumb question, but somehow it's not really clicking. I read somewhere that:... T 12:15 AM WWGD 1 56 We know that a function f(x) over an interval a, b] can be written as an infinite weighted sum over some set of basis... Y 12:34 PM WWGD 15 246 Is there any analytical way to prove that the integral \int_{2.04}^\infty \frac{\sin x}{x^2}dx is nonegative? I... Y 12:28 PM Mark_M 0 97 What is this integral \int\left(\frac{\mathrm{arcsinh}(ax)}{ax}\right)^{b}dx where a and b are constants. Jul31-14 12:45 PM TheDemx27 4 2,164 Hello, I was wondering if the formula ## \int_{a}^{b} f(x) \, dx \approx \tfrac{b-a}{6}\left. ## for... Jul30-14 11:11 PM olivermsun 1 151 Hello! I'm reading Mary Boa's "mathematical methods in the physical sciences" and I'm on a section about total... Jul30-14 03:17 PM WWGD 1 128 Really hard integrals? ( 1 2 3 ... Last) can someone give me some really hard intergrals to solve? make sure they are in the range of calculus 1-2 (anything... Jul30-14 04:05 AM exo 95 48,255 << Moderator's Note -- Original post (OP) restored after being deleted by the poster >> PLEASE HELP! Does anyone... Jul28-14 10:09 PM berkeman 12 294 Alright, Im here again with another question.... When I have a rational function, let's say (x+4)/(x-2)(x-3) I... Jul28-14 06:48 PM eric_999 3 500 Where k is a constant. I am trying to simplify a problem but the t has constant in front of it that is not one, and... Jul28-14 01:46 PM MartinSTuray 4 332 In attachments, there is a pic of a page, I think there area of sector MOA should be 2π^2/x. Please tell me how this... Jul28-14 11:22 AM gopher_p 5 440 Hi, I just read a physics paper and there it expands signum of a sine function as below: ... Jul25-14 05:58 PM jbunniii 1 360 Hey! In my calculus book they claim that a second degree polynomial always can be rewritten as x^2 - a^2 or as x^2... Jul25-14 04:33 PM AlephZero 1 297 So I'm struggling if I should interpret the integral as a sum of infinitesimally small quantities or as just the... Jul24-14 02:12 PM homeomorphic 13 1,554 consider this IVP y'=r-ky , y(0)=y0 y= (y0)e^(-kt) + (r/k)(1-e^(-kt)) if y,y0,r,t are provided, we should be able... Jul24-14 01:51 PM da_nang 2 1,712 Hey! I have this integral: ∫((1/2)/(2x-1))dx. The first time, I did like this: ∫((1/2)/(2x-1))dx = ... Jul24-14 01:03 PM eric_999 3 375 I have had some trouble with Kleppner and Kollenkow's derivation of work in a uniform force field. As the attached... Jul24-14 06:30 AM vanhees71 8 675 17.3-(17.3)e^(-92.34940680845194549420x)^y)=17.30181504460159157646-((17.3-(17.3)e^((-0.00118329948908244714x)^y)) ... Jul23-14 01:01 PM Ledsnyder 2 538 Is a function with a removable discontinuity considered continuous? I've looked through about 6 calculus texts and... Jul22-14 04:25 PM WWGD 11 1,255 Hello everyone. Last week I had an exam in advanced calculus. One of the questions asked about the continuity of a... Jul20-14 03:59 AM verty 3 821 Hello, Can someone show me how the inverse Phasor transform of the sum of individual Phasors of sinusoidal... Jul19-14 11:11 PM olivermsun 8 1,356 Hi Guys, I am revising for an exam i have this week, the last module on my subject was calculus. I did not... Jul19-14 11:01 PM TitoSmooth 7 1,085 Can anyone explain this to me? What does if mean that the area may sometimes be negative but that the area must be... Jul19-14 10:48 PM TitoSmooth 7 1,460 I think I may have found an error in the text I'm reading. Here's a quote: ... + \int_0^{\infty}x^rf_1(x)sin(2\pi... Jul19-14 12:59 PM Mogarrr 20 3,047 Hello, We know that surface integrals come to the form of a surface integral of a scalar function over a surface... Jul19-14 08:48 AM Hertz 5 1,179 Hello Forum, I am familiar with the arithmetic sequence (the difference between one entry and the previous one is... Jul17-14 04:26 PM NathanaelNolk 4 969 To find E |X| of a cauchy random variable, I need to integrate \int_{-\infty}^{\infty}\frac1{\pi}\frac{|x|}{1+x^2}dx... Jul17-14 12:33 PM Mogarrr 3 1,164 Hi, so this is just a quick question about taking a derivative of an integral. Assume that I have some function of... Jul16-14 06:34 PM gopher_p 1 1,055 I have a few questions about the generalizations of concepts like integration and differentiation of single-valued... Jul16-14 03:13 PM jambaugh 3 2,327 Hey all, this is my first post here, I have a question that is kind of annoying me: I came across this equation: ... Jul16-14 11:13 AM Erland 1 1,148 $$\int \sqrt{f(x)}dx$$ is NOT the same as.. $$\sqrt{\int f(x)dx}$$ right? i did an example problem and they... Jul16-14 11:12 AM iScience 4 1,332 Hi everyone. Recently, I came across a closed form solution to ∫|cos(x)|dx as sin(x-∏*floor(x/∏+1/2)) +... Jul16-14 03:28 AM D H 1 1,329 Hi everyone, first post. Anyway, I am reviewing my math physics, and I am having trouble understanding the Divergence... Jul15-14 01:21 PM the_wolfman 3 1,647 A few months ago, I stumped my Mathematics teacher with a question when we were learning about displacement of a... Jul15-14 07:59 AM FilupSmith 6 1,370 Differentiation by first principles is as followed: $$y'=\lim_{h\rightarrow 0}\dfrac {f\left( x+h\right) -f\left(... Jul15-14 04:45 AM FilupSmith 7 1,802 Hi, When we have \frac{\partial}{\partial r}(r\frac{\partial p}{\partial r})=0 and we get r\frac{\partial... Jul14-14 01:35 PM statdad 1 1,236 My question is related to the exponential growth and decay formula Q=Ae^(kt). Simply, why is the value e used as... Jul14-14 12:21 PM HallsofIvy 6 1,411 Is the following statement valid? sinh{x^2}=\frac{e^{x^2}-e^{x^2}}{2} Reason I ask cause I know that... Jul13-14 05:25 PM HakimPhilo 2 1,681 Let's say we have a function F(\vec{r})=F(s, \phi, z). Then (correct me if I'm wrong): \frac{dF}{dx}=\frac{\partial... Jul12-14 06:44 AM TSC 5 2,840 As part of a physics calculation, I have the following integral$$\int d \bar x a^{\sigma} \left, with Einstein... Jul10-14 03:16 PM Fredrik 9 2,276