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Exercise 1210Calculus › Multivariable calculus › Vector calculusL1Added 3 Nov 2026

Conservative vector field

#conservative#gradient#path independence

Statement

Show that F⃗(x,y)=(2x,2y)\vec F(x,y)=(2x,2y) is conservative and compute ∫CF⃗⋅dr⃗\int_C\vec F\cdot d\vec r along any path from (0,0)(0,0) to (1,2)(1,2).

Hint

Find a potential ϕ\phi with ∇ϕ=F⃗\nabla\phi=\vec F.

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Solution

Potential. ϕ(x,y)=x2+y2\phi(x,y)=x^2+y^2 satisfies ∇ϕ=(2x,2y)=F⃗\nabla\phi=(2x,2y)=\vec F.

Path independence. Integral =ϕ(1,2)−ϕ(0,0)=1+4=5=\phi(1,2)-\phi(0,0)=1+4=5.

Conclusion. The field is conservative; integral =5=5 regardless of path.