Why does the Biot-Savart law use both r and r-hat?

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Astrum
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I'm not sure I get how:[tex]\frac{\mu_{0}}{4\pi}\int_{C}\frac{I(d\vec{l}\times\vec{r})}{r^{3}}[/tex] = [tex]\frac{\mu_{0}}{4\pi}\int_{C}\frac{I(d\vec{l}\times\hat{r})}{r^{2}}[/tex]

the r is a displacement vector in the first, and in the second it's a unit vector, but why is this so?
 
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The second expression is correct, the first one is not.
 
There's nothing really to get: [itex]\widehat{r} = \frac{ \vec{r} }{r}[/itex].
 
I see,another dumb question I asked, sorry for wasting your time...