$$D_r=\left\{-1,0\right\}$$  

$$D_r=\left\{-1,1\right\}$$  

$$D_r=\left\{-1,1,4\right\}$$  

$$D_r=\left\{-1,0,1\right\}$$  

$$R_r=\left\{2,1,4\right\}$$  

$$R_r=\left\{2,1,2\right\}$$  

$$R_r=\left\{2,1\right\}$$  

$$R_r=\left\{2,0\right\}$$  

$$r\ =\ \left\{\left(x,y\right)\in A\times A\rceil xy=y\right\}$$  

$$r\ =\ \left\{\left(x,y\right)\in A\times A\rceil\frac{x}{y}=3\right\}$$  

$$r\ =\ \left\{\left(x,y\right)\in A\times A\rceil x-y=6\right\}$$  

$$r\ =\ \left\{\left(x,y\right)\in A\times A\rceil x+y=6\right\}$$  

$$D_r=R$$  

$$D_r=\left[-4,4\right]$$  

$$R_r=R$$  

$$R_r=\left[-4,4\right]$$  

$$r^{-1}=\left\{\left(x,y\right)\in R\times R\rceil y=3x+4\right\}$$  

$$r^{-1}=\left\{\left(x,y\right)\in R\times R\rceil y=\frac{x+4}{3}\right\}$$  

$$r^{-1}=\left\{\left(x,y\right)\in R\times R\rceil y=3x-4\right\}$$  

$$r^{-1}=\left\{\left(x,y\right)\in R\times R\rceil y=\frac{x-4}{3}\right\}$$  

[0,7]

$$\left(-\infty,-7\right]\cup\left[7,\infty\right)$$  

(-7,7)

[-7,7]

$$\left(-\infty,-5\right)\cup\left(5,\infty\right)$$  

$$\left(-\infty,-5\right]\cup\left[5,\infty\right)$$  

$$\left[-5,5\right]$$  

$$\left(-5,5\right)$$  

$$r_1\subset r_2$$  

$$r_2\subset r_1$$  

$$r_1\subset r_2^{-1}$$  

$$r_2\subset r_1^{-1}$$  

$$\left(-\infty,0\right)\cup\left(4,\infty\right)$$  

$$\left(-\infty,0\right]\cup\left[4,\infty\right)$$  

$$\left(0,4\right)$$  

$$\left[0,4\right]$$