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amperes law question..

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here is a question:
http://i25.tinypic.com/fc8rqr.jpg

there is endless cylinder i which we only see its crossection in the photo.
its radius is [latex]R_1[/latex] a distance d from the center a cylinder with radius [latex]R_2[/latex]
along the cylinder flows current I in a uniform way inside the page(X).
1.what is the magnetic field in x>0 region?
2.what is the magnetic field in (0,[latex]R_1[/latex])?

i tried to solve it by amperes law
[latex]\oint \vec{B}\vec{dl}=\mu_0 I[/latex]
0<r<d
[latex]\oint \vec{B}\vec{dl}=\mu_0 I\\[/latex]
[latex]I_0=I\frac{\pi r^2}{\pi R_1^2}=I\frac{ r^2}{R_1^2}\\[/latex]
[latex] B =\mu_0 I\frac{ r^2}{R_1^2 2\pi r}\\[/latex]

have i done the first region correctly
 
dl vector is the way we are going
but we can go clock wise and counter clock wise
and in each case i will have a different result
??
 
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