Evaluation of the given integral for the given surface

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I need to calculate the integral:

$$\iiint_E \sqrt{x^2+z^2}\,dV$$

such that $E$ is the solid bounded by $y=x^2+z^2$ and $y=4$.

I am not able to decide the limits of integration, a walk through for this would be really appreciated. Additionally, is there a way I can solve this using cylindrical co-ordinates?

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HINT

Let use cylindrical coordinates with

  • $x=r\cos \theta$

  • $z=r\sin \theta$

  • $y=y$

  • $dV=r \,dy\, dr\, d\theta$

then

$$\iiint_E \sqrt{(x^2+z^2)}.dV=\int_{0}^{2\pi}d\theta\int_0^4 dy\int_0^{\sqrt y}r^2 \, dr$$

In cartesian coordinates we have

$$\iiint_E \sqrt{(x^2+z^2)}.dV=\int_{0}^{4}dy\int_{-\sqrt y}^{\sqrt y} dx\int_{-\sqrt{y-x^2} }^{\sqrt{y-x^2}}\sqrt{x^2+z^2}\, dz$$