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Line Integrals

So, I've just learnt line integrals and I understand that
Unparseable latex formula:

\displaystyle \int_{R}{\vec{F}} \cdot d \vec{r} = \int_{a}^{b} \vec{F}(\mathBB{r}(t)) \cdot \frac{d \vec{r}}{dt} dt

, which would be a scalar.

But I thought that a line integral computes the area above the curve defined by the vector function r(t)\displaystyle \vec{r}(t) and below the function F\displaystyle \vec{F} . But what happens when the line integral is a vector, for example in the question: ϕ=xyz,F=(xy,0,x2),c:(x,y,z)=(t2,2t,t3),t(0,1) \displaystyle \phi = xyz, \vec{F} = (xy,0,x^2), c : (x,y,z) = (t^2,2t,t^3), t \in (0,1) the line integral cϕdr \displaystyle\int_{c} \phi d\vec{r} and cF×dr \displaystyle \int_{c} \vec{F} \times d\vec{r}

are vectors. Why? and what is this calculating?
(edited 5 years ago)
Can you clarify which terms denote vector quantities please?
Original post by DFranklin
Can you clarify which terms denote vector quantities please?


Edited, hopefully it's clearer.

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