Source: Paul's Notes (https://tutorial.math.lamar.edu/Solutions/CalcIII/ChainRule/Prob6.aspx)
In his solutions:
where he computes the stuff in red. My question is, why is $$\frac{\partial y}{\partial p}$$not $$1+3\frac{\partial t}{\partial p}=1+3\left(\frac{-1}{2}\right)=\frac{-1}{2}$$ Thanks
Consider differentiation ##\frac{df(x)}{dx}##. If we change the variable as ##x=-u## how does the differentiation change? Does it change as ##\frac{df(-u)}{-du}##?
I am reading the Lancaster & Blundell, Quantum field theory for gifted amateur, p.225 and stuck at understanding some derivations.
We will calculate a generating functional for the free scalar field. The free Lagrangian is given by
$$ \mathcal{L}_0 = \frac{1}{2}(\partial _\mu \phi)^2 -...
If I'm informed that a structure on a plant is a leaf with a certain number of leaflets, I can usually visualize the plant that way. But if I'm not informed about that fact, I only see leaves. How can I distinguish leaves vs leaflets?
Part (a) no problem...chain rule
##\dfrac{dy}{dx}= (2x+3)⋅ e^{x^2+3} =0##
##x=-1.5##
For part b,
We need to determine and check if ##\dfrac{d^2y}{dx^2}>0##
...
##\dfrac{d^2y}{dx^2}=e^{x^2+3x} [(2x+3)^2+2)]##
Now any value of ## x## will always give us, ##\dfrac{d^2y}{dx^2}>0##
The other...
I want to shed some light on complex analysis without getting all the technical details in the way which are necessary for the precise treatments that can be found in many excellent standard textbooks.
Analysis is about differentiation. Hence, complex differentiation will be my starting point...
This is a text book example- i noted that we may have a different way of doing it hence my post.
Alternative approach (using implicit differentiation);
##\dfrac{x}{y}=t##
on substituting on ##y=t^2##
we get,
##y^3-x^2=0##
##3y^2\dfrac{dy}{dx}-2x=0##
##\dfrac{dy}{dx}=\dfrac{2x}{3y^2}##...
IMPORTANT: NO CALCULATORS
I assumed two points, (a, f(a)) and (b, f(b)) where b is greater than a. Since the tangent line is shared, I did
f'(a) = f'(b):
1) 4a^3 - 4a - 1 = 4b^3 - 4b - 1
2) 4a^3 - 4a = 4b^3 - 4b
3) 4(a^3 - a) = 4(b^3 - b)
4) a^3 - a = b^3 - b
5) a^3 - b^3 = a - b
6) (a...
ok I posted this a few years ago but replies said there was multiplication in it so I think its a mater of format
##\dfrac{\partial u^2}{\partial x\partial y}## is equivalent to ##u_{xy}##
textbook
Hi,
I tutor maths to High School students.
I had a question today that I was unsure of. Can the natural log be to the base 2?
The student brought the question to me from their maths exam where the question was: Differentiate ln(base2) x^2
If the natural log is the inverse of e then how does...
My take;
##6x^2+6y+6x\dfrac{dy}{dx}-6y\dfrac{dy}{dx}=0##
##\dfrac{dy}{dx}=\dfrac{-6x^2-6y}{6x-6y}##
##\dfrac{dy}{dx}=\dfrac{-x^2-y}{x-y}##
Now considering the line ##y=x##, for the curve to be parallel to this line then it means that their gradients are the same at the point##(1,1)##...
The question and ms guide is pretty much clear to me. I am attempting to use a non-implicit approach.
##\tan y=x, ⇒y=\tan^{-1} x##
We know that ##1+ \tan^2 x= \sec^2 x##
##\dfrac{dx}{dy}=sec^2 y##
##\dfrac{dx}{dy}=1+\tan^2 y##
##\dfrac{dy}{dx}=\dfrac{1}{1+x^2}##...
Attempt at question No. 1:
ΔD = ∂D/∂h * Δh + ∂D/∂v * Δv
∂D/∂h = 3Eh^2/(12(1-v^2))
∂D/∂v = 2Eh^3/(12(1-v^2)^2)
Δh = +- 0,002
Δv = 0,02
h = 0,1
v = 0,3
ΔD = 3Eh^2/(12(1-v^2)) * Δh + 2Eh^3/(12(1-v^2)^2) * Δv
Because the problem asked for maximum percentage error then I decided to use the...
We define differentiation as the limit of ##\frac{f(x+h)-f(x)}h## as ##h->0##. We find the instantaneous velocity at some time ##t_0## using differentiation and call it change at ##t_0##. We show tangent on the graph of the function at ##t_0##. But after taking h or time interval as zero to find...
Im going by the chain rule.
I let y=log(t)^2.
T=cos^2x/x^2Dy/DT is 2/t * log(t)
Dt/DX is (sin(2x)/X )((sinx+cosx)/X)
Can someone verify this is the correct way ? As when I multiply dydt by dtdx I get an equation I don't know how to simplify
Hi
For a function f ( x , t ) = 6x + g( t ) where g( t ) is an arbitrary function of t ; then is it correct to say that f ( x , t ) is not an explicit function of t ?
For the above function is it also correct that ∂f/∂t = 0 because f is not an explicit function of t ?
Thanks
First I did drho/dr which is equal to 35.4*10^-12/R. Then I integrated drho by which I got rho=35.4*10^-12. And then the last eqn will be q=rhoV. But the answer was wrong.
I have a doubt on the formula I am using for E because that formula is for a point charge or a charged shell.
$$\sum_i (\frac{\partial}{\partial q_i}(\frac{\partial T}{\partial q_j}\dot{q}_i)+\frac{\partial}{\partial q_i}(\frac{\partial T}{\partial q_j})\ddot{q}_i)+\frac{\partial}{\partial t}(\frac{\partial T}{\partial \dot{q}_j})$$
They wrote that above equation is equal to...
I had an equation. $$T=\frac{1}{2}m[\dot{x}^2+(r\dot{\theta})^2]$$ Then, they wrote that $$\mathrm dr=\hat r \mathrm dr + r \hat \theta \mathrm d \theta + \hat k \mathrm dz$$ I was thinking how they had derived it. The equation is looking like, they had differentiate "something". Is it just an...
Red arrows.
The notes initially say that the error term is positive. After substitution of A and C which are clearly positive, the term suddenly became negative...? Is this a typo, or is there a theory behind this?
Hi PF
A personal translation of a quote from Spanish "Calculus", by Robert A. Adams:
It's about advice on Lebniz's notation1=(sec2y)dydx means dxdx=(sec2y)dydx, I'm quite sure. Why (sec2y)dydx=(1+tan2y)dydx? But I'm also quite sure that the right notation for (sec2y)dydx=(1+tan2y)dydx...
Summary:: help explaining notation with derivatives.
Mentor note: Thread moved from technical section, so no homework template is included
Sorry. I did not realize there was a dedicated homework problem section. Should I leave this post here?
Basically the following (homework) problem. I...
Hi, PF
##y^2=x## is not a function, but it is possible to obtain the slope at any point ##(x,y)## of the equation without previously clearing ##y^2##. It's enough to differentiate respect to ##x## the two members, treat ##y## like a ##x## differentiable function and make use of the Chain Rule...
Hello there, I have found a different central differentiation formula for a first derivate from what I am used to seeing and I was wondering if they were the same one. I am struggling to find the Numerical Differentiation formulas (forward, backward and central) in scholarly articles and I have...
I don't know much about biology but the following two questions have always puzzled me.
1: If each human body cell contains the same genes (from 20,000 to 25,000) then how different cells in different parts of body do different things. A liver cell, for example, does not have the same...
𝝏w/𝝏x=1
and then I wasn't sure about 𝝏x/𝝏s, so I tried implicitly differentiating s:
1=(3x^2)(𝝏x/𝝏s)+y(𝝏x/𝝏s)+x(𝝏y/𝝏s)+(3y^2)(𝝏y/𝝏s)
And then I shaved my head in frustration.
zx = 2xy + y2 -3y = 0 and zy = 2xy + x2 - 3x = 0
Subtracting one equation from the other gives
y2 - 3y = x2- 3x ⇒ y (y-3) = x (x-3)
This leads to the following solutions ( 0 , 0) , (0 ,3) , (3 , 0) but the answer also gives ( 1, 1) as a solution. What have i done wrong to not get this...
Let z = [a b]^T be in the 2-dimensional vector space over real numbers, and T a linear transformation on the vector space.
Consider
$$\lim_{z'\rightarrow \mathbf{0}} \frac{T(z+z')-T(z)}{z'}$$
I argue this could be an alternative definition for complex derivative.
To illustrate this, z as a...
The detailed list of the concepts I should master
I'm attending the last year of high school and I'm currently studying limits.
For university test reasons I'll need to study on my own topics such as differentiation and integration... and I have just 14 days to do so!
Firstly, do you think it's...
The Attempt at a Solution
I know the answer is supposed to be ##(-1,0)##.
However when I differentiate the above expression I get.
$$
2x+{\frac 5 2}
$$
Then the shortest distance would be when the expression equates to 0.
$$
2x+{\frac 5 2}=0
$$
I should be getting ##x=-1## but solving for ##x##...
I am confused about implicit differenciation in a few ways. The main confusion is why, in the equation ## x^2 + y^2 = 1 ##, when we are taking the derivative of the left side, ## 2x + 2yy\prime ##, are we adding a ## y\prime ## to the 2y but we aren't adding an ## x\prime ## to the 2x? I also...
Hello! Based on QCD we can have gluon self-interaction i.e. a vertex with 3 or 4 gluons. What were the experimental evidences by which the existence of these vertices was confirmed? Also, how does one differentiate between a quark and a gluon induced jet? Thank you!
I have attached a photograph of my workings. I do not know if I have arrived at the right solution, nor whether this is the gradient of f(x) at point P.
I think I seem to overcomplicate these problems when thinking about them which makes me lose confidence in my answers. Thank you to anyone who...
Hi everyone.
I am studying Chebyshev Polynomials to solve some differential equations. I found in the literature that if you have a function being expanded in Chebyshev polynomials such as
$$
u(x)=\sum_n a_n T_n(x),
$$
then you can also expand its derivatives as
$$
\frac{d^q u}{dx^q}=\sum_n...
How are different elements spectral lines naturally 'scrambled' and then differentiated by observation, into each and every element contained in a 'single' light beam emanating from a light source? Is the term 'single' correct in this context and if not can you explain why?
I found a theorem that states that if A and B are 2 endomorphism that satisfies $$[A,[A,B]]=[B,[A,B]]=0$$ then $$[A,F(B)]=[A,B]F'(B)=[A,B]\frac{\partial F(B)}{\partial B}$$.
Now I'm trying to apply this result using the creation and annihilation fermionics operators $$B=C_k^+$$ and $$A=C_k$$...
Summary:: van der waals
I have a pretty good understanding of implicit differentiation. However I'm stuck on a homework problem and could use some help.
[P + (an^2)/V^2][V - nb] = nRT a,n,b,R are constants
My professor wants me to take the implicit differentiation of P wrt...
Hello,
How to find formulas for these$\displaystyle\int x^n\sin(x)\, dx, \displaystyle\int x^n\cos(x)\, dx,$ indefinite integrals when $n=1,2,3,4$ using differentiation under the integral sign starting with the formulas
$$\displaystyle\int \cos(tx)\,dx = \frac{\sin(tx)}{t}...
I am reading Bruce P. Palka's book: An Introduction to Complex Function Theory ...
I am focused on Chapter III: Analytic Functions, Section 1.2 Differentiation Rules ...
I need help with an aspect of Example 1.5, Section 1.2, Chapter III ...
Example 1.5, Section 1.2, Chapter III, reads as...
For this one I did implicit differentiation. Where I then obtained y'=(-2x-4p)/(4x+3p2).
Once I had this I plugged in my values where p is $4 per bag and x is 20 cents.
I plugged in my values y'= (-2(20)-4(4))/(4(20)+3(4)2) =-7/16.
However when I checked this answer it was incorrect and I am...
I am new to calculus. I am doing well in my class. I just have a few questions about implicit differentiation. First, why do we call it "implicit" differentiation?
Also, when we do it, why when we differentiate a term with a "y" in it, why do we have to multiply it by a dY/dX? What does that...
The strategy here would probably be to find a differential equation that ##f## satisfies, but differentiating with respect to ##x## using Leibniz rule yields
##f'=\int_x^{2x} (-te^{-t^2x}) \ dt + \frac{2e^{-4x^3}-e^{-x^3}}{x}##
Continuing to differentiate will yield the integral term again...