Question

2) Suppose the curve C is a circle centred at the origin with radius r > 0.Show that the line integral is only dependent on the radius r of the curve C. \oint_{C}\left(y \sin x+\frac{1}{3} y^{3}-4 y\right) d x+\left(x y^{2}-y-\cos x\right) d y

Fig: 1

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