Is the Parameterization Correct in Leithold's Stokes' Theorem Problem?

runinfang
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Homework Statement
Verify Stokes' theorem in the plane where f(x,y)=y2i+x2j
and the region formed is bounded by the circle (x^2+y^2=4).
Relevant Equations
Stokes' theorem in the plane
"Let \( M \) and \( N \) be the functions, \( C \) be the curve, and \( R \) be the region defined as in Green's theorem. If \( \mathbf{F}(x, y) = M(x, y)\mathbf{i} + N(x, y)\mathbf{j} \) and \( \mathbf{T}(s) \) is the unit tangent vector to \( C \) at \( P \), where \( s \) units is the arc length of \( C \) measured from a point \( P_0 \) to \( P \), then:

\[
\oint_C \mathbf{F} \cdot \mathbf{T} \, ds = \iint_R (\text{curl } \mathbf{F}) \cdot \mathbf{k} \, dA
\]"
The question is a problem from Leithold's calculus book. I didn't understand the (x = 5 \cos(t)). Shouldn't it be (x = 2 cos(t))? I'm referring to item b.
1710974059690.png

i tried this way. i don't know what is wrong.
1710975133627.png
 
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runinfang said:
Homework Statement: Verify Stokes' theorem in the plane where f(x,y)=y2i+x2j
and the region formed is bounded by the circle (x^2+y^2=4).
Relevant Equations: Stokes' theorem in the plane
"Let \( M \) and \( N \) be the functions, \( C \) be the curve, and \( R \) be the region defined as in Green's theorem. If \( \mathbf{F}(x, y) = M(x, y)\mathbf{i} + N(x, y)\mathbf{j} \) and \( \mathbf{T}(s) \) is the unit tangent vector to \( C \) at \( P \), where \( s \) units is the arc length of \( C \) measured from a point \( P_0 \) to \( P \), then:

\[
\oint_C \mathbf{F} \cdot \mathbf{T} \, ds = \iint_R (\text{curl } \mathbf{F}) \cdot \mathbf{k} \, dA
\]"

The question is a problem from Leithold's calculus book. I didn't understand the (x = 5 \cos(t)). Shouldn't it be (x = 2 cos(t))? I'm referring to item b.
View attachment 342076
i tried this way. i don't know what is wrong.
View attachment 342077
Please wrap your text with ## or otherwise to render Latex, make your text more readable.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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