Prove that a subfamily of pairwise disjoint sets is pairwise disjoint

[Willy_Will]

hello,

I really don't know how to proceed here, since I don't know very much about sets/family.

I want to prove that if Ð is a family of pairwise disjoint sets, and Ŧ is a subset of Ð, prove that Ŧ is also a family of pairwise disjoint sets.

Thanks in advance math gurus

William

 

[matt grime]

if x and y are elements of T, then they are elements of D. So what is xny? (n means intersection)

 

[Willy_Will]

if x and y are elements of T, then they are elements of D. because T is a subset of D.

However, xny will be empty set, because they are also elements of D, and D is pairwise disjoint.

T is also pairwise disjoint.

Like that?

 

[ZioX]

Precisely.

 

[Willy_Will]

Thanks guys!