Calculus, originally called infinitesimal calculus or "the calculus of infinitesimals", is the mathematical study of continuous change, in the same way that geometry is the study of shape and algebra is the study of generalizations of arithmetic operations.
It has two major branches, differential calculus and integral calculus; the former concerns instantaneous rates of change, and the slopes of curves, while integral calculus concerns accumulation of quantities, and areas under or between curves. These two branches are related to each other by the fundamental theorem of calculus, and they make use of the fundamental notions of convergence of infinite sequences and infinite series to a well-defined limit.Infinitesimal calculus was developed independently in the late 17th century by Isaac Newton and Gottfried Wilhelm Leibniz. Today, calculus has widespread uses in science, engineering, and economics.In mathematics education, calculus denotes courses of elementary mathematical analysis, which are mainly devoted to the study of functions and limits. The word calculus (plural calculi) is a Latin word, meaning originally "small pebble" (this meaning is kept in medicine – see Calculus (medicine)). Because such pebbles were used for counting (or measuring) a distance travelled by transportation devices in use in ancient Rome, the meaning of the word has evolved and today usually means a method of computation. It is therefore used for naming specific methods of calculation and related theories, such as propositional calculus, Ricci calculus, calculus of variations, lambda calculus, and process calculus.
I'm looking for good books on Tensors.
I have "Introduction to Tensor Analysis and the Calculus of Moving Surfaces" from Pavel Grinfeld.
But i look for others.
[Mentor Note: Thread moved from the Relativity forum]
Hi everyone, I'm a new here, this is my presentation https://www.physicsforums.com/threads/new-self-study-member.1061374/
I want to study physics for my own intrest and understanding of the universe. A few years ago, after high-school, I studied Halliday and Resnick quite thoroughly, both...
STARTING IPHO. Hi guys, I am going to grade 10 this year and wanted to start physics olympiad preparation from basics. I dont know calc 1 too. Can you suggest me a good calculus book to get my hands on? Moreover, is it late to start my preparation? Thanks in advance.
My hypothesis:
The number of red giants is equal to the number of stars times the given fraction f.
The number of stars in a solid angle omega, is given by the density distribution of stars in the Galaxy times the volume of the observed solid angle:
#RG = f*n(r)*V
where V = (d^3*omega)/3.
I...
I'm trying to pace myself to get up to speed with my calc and physics before going back to college. It's been so long that I don't know how much we got up to in calc I. Can someone tell me what chapter in Thomas Calculus does calc I go up to, or do they cover the whole thing?
I would like to take the derivative of the following function with respect to Gt:
$$\mathrm{G}_{t+1}=\mathrm{g}_{0}\mathrm{e}^{-qHt}$$
I think that the answer is either -1 or ##\mathrm{e}^{-qHt}-1##
If you could show the calculations that would be a great help.
Thanks very much.
My lines are as follows;
##y=\sqrt x## and ##y=x^2## intersect at ##(0,0## and ##(1,1)##.
Along ##y=\sqrt x##, from ##(0,0)## to ##(1,1)## the line integral equals,
$$\int_0^1 [3x^2-8x] dx + \dfrac{4\sqrt x-6x\sqrt x}{2\sqrt x} dx $$
$$=\int_0^1[3x^2-8x+2-3x]dx=\int_0^1[3x^2-11x+2]dx =...
I'm trying to brush up on my algebra, trig, and calculus, and one thing I know I was always weak on before was proofs. I was never sure what equations would suffice as "proof," and which equations did not. Maybe this is an inane question, and maybe there is a really simple answer to this. I...
In free time I start to solve differentials and integrals, I am doing fine, I just follow rules and solve the tasks.
I start solve some applied calculus tasks, but I dont really understand why for exmple second derivative represent acceleration, why first is speed, why I need to derivate...
Like the title and the summary suggest, I can derive the volume ##V=2\,\pi^{2}\,r^{2}\,R## for a ring torus - a doughnut-style toroid (one such that the major radius ##R## > the minor radius ##r##, and it therefore has a hole at the center) that is of circular cross-section. But I want to be...
Hi all currently got a lagrangian function which i've found to be :
\begin{equation}\mathcal{L}=\frac{1}{2}m(\dot{x}^2+\dot{y}^2+4x^2\dot{x}^2+4y^2\dot{y}^2+8xy\dot{x}\dot{y})- mg(x^2+y^2)
\end{equation}
Let us first calculate
$$(\frac{\partial L}{\partial \dot{x}})$$ which leads us to...
To use the formula above, I have to prove that $$\lim_{n\rightarrow \infty}f(x)=\lim_{n\rightarrow \infty}\left(\frac{1+\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+........\frac{1}{n}}{n^2}\right)=1$$
To prove so, I tried using L'Hopital's Rule:
$$\lim_{n\rightarrow \infty}f(x)=\lim_{n\rightarrow...
Hi;
please see below I am trying to understand how to get to the 2 final functions. They should be the same but 6 for the first one and 2 for the second?
(I hope my writing is more clear than previously)
There is an additional question below.
thanks
martyn
I can't find a standard derivative...
(Disclaimer: I don't know whether this type of post encouraging discussion on a function is allowed, if not please close this)
Hello PF,
If you're a fan of integrating, you'll hit a ton of special functions on the way. Things like the Harmonic Numbers, Digamma function, Exponential Integral...
##(f(c) - f(a))((f)(b) - f(c)) <0## tells us that there are two cases:
##f(c) >f(a), f(b) ##
##f(c) <f(a), f(b) ##.
I guess we need to define a new function here that let us use the Rolle's theorem..
But it is not clear enough how to do so.
Hello PF!
This is my very first post here. Just yesterday my paper was accepted by ArXiV, called "A Simple Continuation for Partial Sums". If you have time (it's 14 pages) you can take a look at it here. I was just interested in ways I could improve my paper or if it was completely useless in...
I proceeded as follows
$$\int\frac{2(\sqrt3-1)(cosx-sinx)}{2(\sqrt3+2sin2x)}dx$$
$$\int\frac{(cos(\pi/6)-sin(\pi/6))(cosx-sinx)}{(sin(\pi/3)+sin2x)}dx$$
$$\frac{1}{2}\int\frac{cos(\pi/6-x)-sin(\pi/6+x)}{sin(\pi/6+x)cos(\pi/6-x)}dx$$
$$\frac{1}{2}\int cosec(\pi/6+x)-sec(\pi/6-x)dx$$
Which leads...
My first thought as well but I think the problem is deeper than that. I think that as the n tends towards infinity the probability of the the sample mean converging to the population mean is 1. Looking at proving this.
By the Central Limit Theorem the sample mean distribution can be approximated...
A question in advance: How do I format equations correctly?
Let's say
$$\mathbf{k}\cdot\nabla\times(a\cdot\mathbf{w}\frac{\partial\,\mathbf{v}}{\partial\,z})$$
- a is a scalar
Can I rewrite the expression such that...
I need help to understand how equation (27) in this paper has been derived.
The definition of P(k) (I discarded in the question ##\eta## or the integration with respect for it) is given by (26) and the definition of h(k) and G(k) are given by Eq. (25) and Eq. (24) respectively.
In my...
Hi,
I'm not sure if I have calculated task b correctly, and unfortunately I don't know what to do with task c?
I solved task b as follows
##\displaystyle{\lim_{\epsilon \to 0}} \int_{- \infty}^{\infty} g^{\epsilon}(x) \phi(x)dx=\displaystyle{\lim_{\epsilon \to 0}} \int_{\infty}^{\epsilon}...
I know the easier method/trick to solve this which doesn't require integration. Since parabola is symmetric about x-axis and direction of current flow is opposite, vertical components of force are cancelled and a net effective length of AB may be considered then ##F=2(4)(L_{AB})=32\hat i##
I...
a)
Consider the functional ## S[y]=\int_{0}^{v}(y'^2+y^2)dx, y(0)=1, y(v)=v, v>0 ##.
By definition, the Euler-Lagrange equation is ## \frac{d}{dx}(\frac{\partial F}{\partial y'})-\frac{\partial F}{\partial y}=0, y(a)=A, y(b)=B ## for the functional ## S[y]=\int_{a}^{b}F(x, y, y')dx, y(a)=A...
Consider the functional ## S[y]=\int_{1}^{2}x^2y^2dx ## stationary subject to the two constraints ## \int_{1}^{2}xydx=1 ## and ## \int_{1}^{2}x^2ydx=2 ##.
Then the auxiliary functional is ## \overline{S}[y]=\int_{1}^{2}(x^2y^2+\lambda_{1}xy+\lambda_{2}x^2y)dx, y(1)=y(2)=0 ## where ## \lambda_{1}...
Are there features of operational calculus (or operator methods) that are advantageous over transforms for DE? I know that the techniques are closely related.
In the book, I see the following:
##\int_{x_1}^{x_1 + \epsilon X_1} F(x, \hat y , \hat y') dx = \epsilon X_1 F(x, y, y')\Bigr|_{x_1} + O(\epsilon^2)##.
My goal is to show why they are equal. Note that ##\hat y(x) = y(x) + \epsilon \eta(x)## and ##\hat y'(x) = y'(x) + \epsilon \eta'(x)## and...
I am trying to grasp how the last equation is derived. I understand everything, but the only thing problematic is why in the end, it's ##+O(\epsilon)## and not ##-O(\epsilon)##. It will be easier to directly attach the image, so please, see image attached.
Here's my work:
Let ## n>1 ## be a positive integer.
Consider the functional ## S[y]=\int_{0}^{1}(y')^{n}e^{y}dx, y(0)=1, y(1)=A>1 ##.
By definition, the Jacobi equation is ## \frac{d}{dx}(P(x)\frac{du}{dx})-Q(x)u=0, u(a)=0, u'(a)=1 ##, where ## P(x)=\frac{\partial^2 F}{\partial y'^2} ## and...
(a) The length ##h = L## for which the tension is minimum is the length that corresponds to the geostationary orbit, where the angular velocity of the cable matches the angular velocity of the Earth. This is because at this point, the centrifugal force balances the gravitational force, and the...
Ok i have,
##f_x= 3x^2-y-1+y^3##
##f_y = -x+3xy^2-4y^3##
##f_{xx} = 6x##
##f_{yy} = 6xy - 12y^2##
##f_{xy} = -1+3y^2##
looks like one needs software to solve this?
I can see the solutions from wolframalpha: local maxima to two decimal places as;
##(x,y) = (-0.67, 0.43)##
...but i am...
My interest is on number 11.
In my approach;
##v= xyz##
##1000=xyz##
##z= \dfrac{1000}{xy}##
Surface area: ##f(x,y)= 2( xy+yz+xz)##
##f(x,y)= 2\left( xy+\dfrac{1000}{x} + \dfrac{1000}{y}\right)##
##f_{x} = 2y -\dfrac{2000}{x^2} = 0##...
Hi.
What exactly is happening mathematically when you integrate ##\frac{1}{x}##
$$\int_a ^b \frac{1}{x} dx=\ln{b}-\ln{a}=\ln{\frac{b}{a}}$$
if there's units? Sure, they cancel if you write the result as ##\ln{\frac{b}{a}}##, but the intermediate step is not well-defined, so why should log rules...
I want to prove that ##(a+b)\cdot c=a\cdot c+b\cdot c## using Peano postulates where ##a,b,c \in \mathbb{N}##.
The book I am using ("The real numbers and real analysis" by Ethan Bloch ) defines Peano postulates little differently.
Following is a set of Peano postulates I am using. (Axiom 1.2.1...
I have to prove ##a \cdot 1 = a = 1 \cdot a## for ##a \in \mathbb{N}##.
The book I am using ("The real numbers and real analysis" by Ethan Bloch) defines Peano postulates little differently.
Following is a set of Peano postulates I am using. (Axiom 1.2.1 in Bloch's book)
There exists a set...
Hi
I have to prove the following three tasks
I now wanted to prove three tasks with a direct proof, e.g. for task a)$$\sqrt[n]{n} = n^{\frac{1}{n}}= e^{ln(n^{\frac{1}{n}})}=e^{\frac{1}{n}ln(n)}$$
$$\displaystyle{\lim_{n \to \infty}} \sqrt[n]{n}= \displaystyle{\lim_{n \to \infty}}...
I have a two volume set of Differential and Integral Calculus textbooks by a well-known mathematician, his second edition (1959 printing) the last of twenty printings. This set was recommended by one of my math professors. Although it was my intention to read them it was not to be. Below is a...
I have a model for airs density as a function of height
I would imagine the speed can be describes as the angular velocity times length
The coefficient of drag can be found online, seems to be around 1.17 for a cylinder
It seems to me that im going to need an integral somewhere, but can't quite...
I have troubles finding the limits at the designated points , should i only find the limit at infinity where f(x) has belongs to an interval containing inifinity? (sorry for english)
and for the a this is what i attempted. i am unsure.
Our textbook never talks about piecewise functions and...
Hi PF,
$$\int \cos ax\,dx,\quad a\in{\mathbb R-\{0\}}\quad x\in{\mathbb{R}}$$
Let's make
$$u=ax,\quad du=adx$$
and apply $$\int \cos u\,du=\sin u+C$$
$$\frac{1}{a}\int \cos ax\,adx=\frac{1}{a}\sin u+C$$
Substituting the definition of u
$$=\frac{1}{a}\sin ax+C$$
Doubts:
(i) Have I written well...
Here is the homogenous paper rectangle
And if we roll it we get a cylinder with base radius ##a##.
It is not clear to me what "an axis through a diameter of the circular base means".
Let's imagine such as axis is ##\alpha## in the following figure
Then we have...
Was solving a problem in mathematics and came across the following integration. Unable to move further. Can somebody provide answer for the following ( a and b are constants ).
I was able to solve it using,
##\dfrac{dV}{dt} = \dfrac{dV}{dh}⋅\dfrac{dh}{dt}##
With, ##r = \dfrac{h\sqrt{3}}{3}##, we shall have
##\dfrac{dV}{dh} = \dfrac{πh^2}{3}##
Then,
##\dfrac{dh}{dt}= \dfrac{2×3 ×10^{-5}}{π×0.05^2}= 0.00764##m/s
My question is can one use the ##\dfrac{dV}{dt} =...
In my approach i have distance as ##(x)## and velocity as ##(x^{'})##, then,
##(x^{'}) = kx^2##
where ##k## is a constant, then acceleration is given by,
##(x^{''}) = 2k(x) (x^{'})##
##(x^{''}) = 2k(x)(kx^2) ##
##(x^{''}) = 2k^2x^3##.
Correct?
The Math challenge threads have returned!
Rules:
1. You may use google to look for anything except the actual problems themselves (or very close relatives).
2. Do not cite theorems that trivialize the problem you're solving.
3. Do not solve problems that are way below your level. Some problems...