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

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The discussion revolves around evaluating the integral expression involving the components of a force field, specifically ##\int_0^1 F_x(x,0)dx + \int_0^1 F_y(1,y)dy##, where ##F = (y, 2x)##. Participants express confusion about how to interpret and compute the integrals, particularly regarding the values of ##F_x## and ##F_y##. Clarifications are sought on the meaning of setting variables to specific values within the integrals and the implications of the scalar product. The conversation highlights the need for understanding the relationship between the force components and the integration limits. Overall, the thread emphasizes the complexities of evaluating integrals in vector fields.
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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##
 
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EpselonZero said:
Why not y = 0 in the first integral?
I think that's what @pasmith meant to write.
 
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