PLEASE HELP with set theory

jabronieman316 · New Member Offline Joined: 30 Jan 2005 Posts: 3

Hi,

Can anybody help out with the following problems: please
Sorry if it in the wrong forum

1. Prove that the following property holds

(a,b)=(a1,b1) if and only if a=a1 and b=b1

2. Are we justified in calling the partial function from X->Y and the total functions from X->Y sets, where X and Y are sets?

3. Show that for any sets X and Y, where Y has atleast 2 elements, that there canot be a 1 to 1 corrospondence between X and the set of functions (X->Y)

4. Let R be a realtion on a set X. We write Rop as the opposite or converse relation where Rop = {(y,x) | (x,y) belongs to R}}
Show that (R U Rop)* is an equivalance realtion and R U (Rop)* need not be an equivalance relation.

Thank you for any help at all

**Posted:** Sun Jan 30, 2005 11:20 am

jabronieman316 · New Member Offline Joined: 30 Jan 2005 Posts: 3

can anybody help out?

please

**Posted:** Mon Jan 31, 2005 8:34 pm

Valentin Vornicu

this doesn't look anything like advanced fields to me. I'll move it to a more appropriate forum ...

**Posted:** Tue Feb 01, 2005 12:23 am

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ComplexZeta

Where are these problems from?

**Posted:** Tue Feb 01, 2005 5:47 am

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$\mathbb{C}\zeta$
Simon Rubinstein-Salzedo

jabronieman316 · New Member Offline Joined: 30 Jan 2005 Posts: 3

Glenn Winskel Formal semantics book

**Posted:** Tue Feb 01, 2005 7:09 am

ComplexZeta

Is it a homework assignment?

**Posted:** Tue Feb 01, 2005 10:06 am

_________________
$\mathbb{C}\zeta$
Simon Rubinstein-Salzedo