Question

2. Let a, b be positive real numbers. Calculate following integrations: \iint_{D}\left(x^{2}+y^{2}\right) d x d y \text { where } D=\left\{(x, y) \in \mathbb{R}^{2} \mid \frac{x^{2}}{a^{2}}+\frac{y^{2}}{b^{2}} \leq 1\right\} \iiint_{V} x^{4} d x d y d z \text { where } V=\left\{(x, y, z) \in \mathbb{R}^{3} \mid x^{2}+y^{2}+z^{2} \leq a^{2}\right\}

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