##\int_0^1 F_x(x,0)dx + \int_0^1 F_y(1,y)dy##

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Homework Help Overview

The discussion revolves around evaluating integrals involving a vector field, specifically the expressions ##\int_0^1 F_x(x,0)dx## and ##\int_0^1 F_y(1,y)dy##, where ##F = (y, 2x)##. Participants are exploring the nature of these integrals and the components of the vector field.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants are attempting to understand how to evaluate the integrals and question the definitions of ##F_x## and ##F_y##. There is confusion about the origin of the vector field and how to apply the limits of integration. Some participants are unsure about the implications of setting variables to specific values within the integrals.

Discussion Status

The discussion is ongoing, with participants expressing confusion about the setup of the problem and the interpretation of the integrals. Some guidance has been offered regarding the evaluation of the integrals, but multiple interpretations and uncertainties remain.

Contextual Notes

Participants note a lack of clarity on what information is provided versus what is assumed or derived. There is also mention of potential misunderstandings regarding the components of the vector field and the meaning of "respect to" in the context of the integrals.

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Homework Statement
Integral
Relevant Equations
##\int_0^1 F_x(x,0)dx + \int_0^1 F_y(1,y)dy##
Hi,
This is the first time I see this kind of integral. I'm not sure how to resolve it.

##
\int_0^1 F \cdot dr
##

##
\int_0^1 F_x(x,0)dx + \int_0^1 F_y(1,y)dy
##

##F = (y,2x)##
I don't know the values of ## F_x(x,0) ## and ## F_y(1,y)##
 
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EpselonZero said:
Homework Statement:: Integral
Relevant Equations:: ##\int_0^1 F_x(x,0)dx + \int_0^1 F_y(1,y)dy##

Hi,
This is the first time I see this kind of integral. I'm not sure how to resolve it.

##
\int_0^1 F \cdot dr
##

##
\int_0^1 F_x(x,0)dx + \int_0^1 F_y(1,y)dy
##

##F = (y,2x)##
I don't know the values of ## F_x(x,0) ## and ## F_y(1,y)##
It is unclear what of the above you are given and what is your own work. Where did ##F = (y,2x)## come from?
You should be able to perform the integral ##\int_0^1 F_x(x,0)dx##. (I assume you realize it means ##\int_0^1 \frac{\partial F(x,0)}{\partial x}dx##.)
 
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I don't have anymore information. F is a force.
This is a scalar product, but I don't know the value of ##F_x##
 
haruspex said:
It is unclear what of the above you are given and what is your own work. Where did ##F = (y,2x)## come from?
You should be able to perform the integral ##\int_0^1 F_x(x,0)dx##. (I assume you realize it means ##\int_0^1 \frac{\partial F(x,0)}{\partial x}dx##.)
Unless F_x indicates the horizontal component of \mathbf{F}, which is given as y.
 
That's what I thought, but the answer should be 0 + 2, but I don't get that.

##(y,0)\cdot(x,0) \neq 0##

##(0,2x)\cdot(1,y) \neq 2##
 
EpselonZero said:
That's what I thought, but the answer should be 0 + 2, but I don't get that.

(y,0)⋅(x,0)!=0

(0,2x)⋅(1,y)!=2

The question is asking you to sett x = 0 in the integral with respect to x: <br /> \int_0^1 F_x(x,0)\,dx = \int_0^1 0\,dx. Similarly, the question is asking you to set x = 1 in the integral with respect to y.
 
I'm still confuse. Why not y = 0 in the first integral?

In the second integral, I understand x = 1 so 2x = 2 * 1, but what about x? I'm not sure to understand what respect to means.

For me, ##F_y(1,y)## means ## x = 1## and ##y = y## so ## y = y ## and ## x = 2##

At this point, I'm so confuse I'm not even sure what I'm typing.

Basically, the first integral is on the x-axis and the second on the y axis. ##\int_0^1 F \cdot dr + \int_0^1 F \cdot dr## = ## \int_0^1 Fx \cdot (x,0) dx + \int_0^1 Fy \cdot (1,y) dy##

I thought ##Fx## = 1 so ##1(x,0) = x## and ##2x(1,y) = 2x + 2xy##
 
Last edited by a moderator:
EpselonZero said:
Why not y = 0 in the first integral?
I think that's what @pasmith meant to write.
 

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