Respuesta :

Answer:

Step-by-step explanation:

P= {1,3,5,7,9,11,13,21}

R ={2,4,6,8,10,12}

O={3,6,9,12,15,18}

The union of two sets contain all the elements in  either set.

R ∪ O = {2,4,6,8,10,12,3,9,15,18 }      [6 & 12 are in both R and O. we have to write only one time]

P U (R ∪ O) = {1,3,5,7,9,11,13,21,2,4,6,8,10,12,15,18}