$$\,\,\iint\limits_{\textcolor{lime}{\mathbf{\mathbb{D}}}:\,y = x,\,y = \pi,\,x = 0}\,\cos{\left(x + y \right)}\,dx\,dy$$

$$\,\,\iint\limits_{\textcolor{lime}{\mathbf{\mathbb{D}}}:\,y = 6 x^{2} - 4,\,y = 20}\,f{\left(x,y \right)}\,dx\,dy$$

$$\,\,\iint\limits_{\textcolor{lime}{\mathbf{\mathbb{D}}}:\,- y \leq x \leq - y,\,0 \leq y \leq 1}\,12 y\,dx\,dy$$

$$\,\,\iint\limits_{\textcolor{lime}{\mathbf{\mathbb{D}}}:\,x = 2,\,y = x,\,x y = 1}\,\frac{x^{2}}{y^{2}}\,dx\,dy$$

$$\,\,\iint\limits_{\textcolor{lime}{\mathbf{\mathbb{D}}}:\,x^2+y^2 \lt 1}\,\frac{e^{\sqrt{x^{2} + y^{2}}}}{\sqrt{x^{2} + y^{2}}}\,dx\,dy$$

$$\,\,\iint\limits_{\textcolor{lime}{\mathbf{\mathbb{D}}}:\,1 \leq x^{2} + y^{2} \leq 9,\,y \leq 0,\,x \geq 0}\,\frac{x - y}{x^{2} + y^{2}}\,dx\,dy$$

$$\int\limits_{0}^{2 \phi}\int\limits_{\sin{\left(\phi \right)}}^{1} \frac{2 \rho^{2}}{\phi}\, d\rho\, d\phi$$

$$\int\limits_{0}^{\frac{4}{5}}\, dy\int\limits_{\frac{1}{4}}^{1} \left(x + y\right)\, dx$$

$$\,\,\iint\limits_{\textcolor{lime}{\mathbf{\mathbb{D}}}:\,y = x^{2} + 2,\,y = 1 - x^{2},\,x = 0,\,x = 1}\,1\,dx\,dy$$

$$\int\limits_{0}^{2}\, dy\int\limits_{y}^{2 y} \left(x^{3} + y^{3}\right)\, dx$$

$$\int\limits_{0}^{1}\int\limits_{\frac{\left(-1\right) x}{3}}^{\frac{x}{2}}\int\limits_{\frac{\left(-1\right) y}{2}}^{\frac{y}{3}} z \sqrt{x^{2} + y^{2}}\, dz\, dy\, dx$$

$$\int\limits_{\mathbf{K}} y \,ds$$

$$\int\limits_{\mathbf{K}} \left(\frac{x}{\sqrt{x^{2} - x + y^{2} - y + z^{2} + 2 z}} - \frac{1}{\sqrt{x^{2} - x + y^{2} - y + z^{2} + 2 z}}\right) \,dx + \left(\frac{y}{\sqrt{x^{2} - x + y^{2} - y + z^{2} + 2 z}} + \frac{1}{\sqrt{x^{2} - x + y^{2} - y + z^{2} + 2 z}}\right) \,dy + \left(\frac{z}{2 \sqrt{x^{2} - x + y^{2} - y + z^{2} + 2 z}}\right) \,dz$$

$$\oint\limits_{\mathbf{K}} \left(x y - 1\right) \,dx + \left(x^{2} - y\right) \,dy$$