| $\int_{-1}^1\int_{-\sqrt{1-x^2}}^{\sqrt{1-x^2}} dy dx $ | $\qquad \int_0^1 \int_0 ^{\sqrt{1-y^2}} (x^2+y^2) dx dy $ |
| $\int_{-1}^0\int_{-\sqrt{1-x^2}}^0 \frac{2}{1+\sqrt{x^2+y^2}} dy dx $ | $ \qquad \int_{-1}^1 \int_{-\sqrt{1-y^2}}^0 \frac{4 \sqrt{x^2+y^2}}{1+x^2+y^2} dx dy $ |
| $\int_0^2 \int_0^{\sqrt{1-(x-1)^2}} \frac{x+y}{x^2+y^2} dy dx $ | $ \qquad \int_0^{ ln 2 } \int_0^{\sqrt{ ln^2 {2} -y^2}} e^{\sqrt{x^2+y^2}} dx dy $ |
| $\int_{-2}^0\int_0^{\sqrt{4-x^2}} \frac{2}{(1+x^2+y^2)^2} dy dx $ | $ \qquad \int_{-1}^1 \int_{-\sqrt{1 -y^2}}^{\sqrt{1 -y^2}} \ln (x^2+y^2+1) dx dy $ |
| $ \qquad \int_0^3 \int_0^{\sqrt{9 -y^2}} cos (x^2+y^2) dx dy $ |