Question

dado el universo U={1;2,3,4}y las relaciones R1={(x;y) ϵ U2 x=y} R2={(x;y)ϵ U2/ y=3} R3 = {(x;y) ϵ U2 / x≤y} hallar R3-(R1 ∪ R2)

Answer 1

 U={1;2,3,4}

 

R1={(x;y) ϵ U2 x=y} ---> {(1,1)(2,2)(3,3)(4,4)}

R2={(x;y)ϵ U2/ y=3}  --->  {(1,3)(2,3)(3,3)(4,3)}

R3 = {(x;y) ϵ U2 / x≤y} ---> {(1,2)(1,3)(1,4)(2,3)(2,4)(3,4)}

 

hallar R3-(R1 ∪ R2)

 

R1 ∪ R2 =  {(1,1)(1,3)(2,3)(2,2)(3,3)(4,3)(4,4)}

 

 R3-(R1 ∪ R2)=  {(1,2)(1,4)(2,4)(3,4)}

 

se le quito solo los que se repetian