Integration by Parts in 2D: How to Apply the Rule in Polar Coordinates?

soks
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The integration by parts rule in two dimensions is
\int_{Ω}\frac{\partial w}{\partial x_{i}} v dΩ = \int_{\Gamma} w v \vec{n} d\Gamma - \int_{Ω} w \frac{\partial v}{\partial x_{i}} dΩ

I have two examples in polar coordinates
In first example I have \vec{n}=\vec{n_{r}}

\int_{\Gamma} \frac{1}{r^{2}} \frac{\partial^{2}w}{\partial\varphi^{2}}\frac{∂ v}{\partial r} \vec{n_{r}} d\Gamma = -2 \int_{Ω}\frac{1}{r^{3}}\frac{\partial^{2} w}{\partial \varphi^{2}} \frac{∂v}{∂r} dΩ + \int_{Ω}\frac{1}{r^{2}}\frac{\partial^{3} w}{∂r \partial \varphi^{2} } \frac{∂v}{∂r} dΩ + \int_{Ω}\frac{1}{r^{2}}\frac{\partial^{2} w}{\partial \varphi^{2} } \frac{∂^{2}v}{∂r^{2}} dΩ

and in second \vec{n}=\vec{n_{\varphi}}

\int_{\Gamma} \frac{1}{r^{2}} \frac{\partial w}{\partial\varphi}\frac{∂ v}{\partial r} \vec{n_{\varphi}} d\Gamma = \int_{Ω}\frac{1}{r^{3}}\frac{\partial^{2} w}{\partial \varphi^{2}} \frac{∂v}{∂r} dΩ + \int_{Ω}\frac{1}{r^{3}}\frac{\partial w}{\partial \varphi} \frac{∂^{2}v}{∂r∂\varphi} dΩ

When I integrate with respect to \varphi I multiply equation by \frac{1}{r} but I am no sure if this is correct.

Are this two solutions correct?

Thanks for answers
 
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Functions w and v are functions of r and \varphi ( w = w(r, \varphi) and v = v(r, \varphi))
 
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