Greens theorem-help setting up correct integral

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SUMMARY

This discussion focuses on applying Green's Theorem to evaluate the line integral \(\oint \mathbf{F} \cdot d\mathbf{r}\) for a closed triangular curve defined by vertices P1(0,5), P2(0,2), and P3(3,5). The vector field is given as \(\mathbf{F}(x,y) = xy^2 \mathbf{i} + 4xy \mathbf{j}\). The user calculated the partial derivatives and set up the double integral \(\int\int (4y - 2xy) \, dA\), but faced confusion regarding the limits of integration due to the counterclockwise orientation of the curve. The correct limits should reflect the orientation, specifically \(y\) from 5 to 2 and \(x\) from 0 to \(y-2\).

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Homework Statement


Use Green Theorem to calculate \oint\widehat{}F \bullet d\widehat{}r where C is the closed triangular curve oriented counterclockwise with verticies P1(0,5), P2(0,2) and P3(3,5). vectorF(x,y)= xy^2 i + 4xy j


Homework Equations





The Attempt at a Solution


I first took the partial of F2 with respect to x = 4y
partial of F1 with respect to y = 2xy

\int\int4y-2xy dA

I am not sure of what limits to use:
because it is oriented counter clockwise:
y-2\leq x \leq 0
5 \leq y \leq 2
 
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It looks fine except I would check your order of limits--it should be entering at x=0 and leaving at x=y-2 and it's backwards for y too--maybe that was just a mistake when you wrote it.
 
that is how I did the problem initially however, the problem says it is in the counterclockwise direction which I would think y goes from 5 to 2, and x from 0 to y-2.
(which is only half of what I did)

Can anyone explain this?
 
When you integrate a region, you do so on an interval x\in [a,b],y\in [c,d]. Does the integral make sense if a>b, c>d?
 

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