Theory question about Exact Eqtns and Calculus

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Homework Statement



I've noticed that exact equations take the same form as vector field dot <dx,dy> form, are there any relationships? Because I ended up writing an arrow on top of my F(x,y) everytime I do these exact equation problems

Is there a secret my book is not telling me?
 
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not sure if i understand the question, but if you have a differential
[tex]dQ = A(x,y)dx + B(x,y)dy[/tex]

and they satisfy
[tex]\frac{A(x,y)}{dy} = \frac{B(x,y)}{dx}[/tex]

then there exists a scalar function Q(x,y), such that dQ
[tex]dQ = A(x,y)dx + B(x,y)dy[/tex]

similarly if you consider the vector field
[tex]F = \begin{pmatrix} A(x,y) \\ B(x,y)\end{pmatrix}[/tex]
a line integral will independent of path, depending only on endpoints and equal to [itex]Q(\vec{x}_f) - Q(\vec{x}_i)[/itex], and you could write:
[tex]dQ = F \bullet \vec{dx}[/tex]