MathCastle
Multivariable CalculusMediumDouble Integrals

Double Integrals · Medium problem

Let AA be the annulus 1≤x2+y2≤41 \le x^2 + y^2 \le 4. Evaluate ∬A1x2+y2 dA\displaystyle\iint_A \dfrac{1}{x^2 + y^2}\,dA. Give an exact answer.