Let A = {4, 5, 6} and B = {5, 6, 7} and define relations R,
S, and T from A to B as follows:
For all (x, y) ∈ A × B,
(x, y) ∈ R means that x ≥ y.
(x, y) ∈ S means that
x − y/ 2
is an integer.
T = {(4, 7), (6, 5), (6, 7)}.
a. Draw arrow diagrams for R, S, and T .
b. Indicate whether any of the relations R, S, and T are
functions.

Question

Let A = {4, 5, 6} and B = {5, 6, 7} and define relations R,
S, and T from A to B as follows:
For all (x, y) ∈ A × B,
(x, y) ∈ R means that x ≥ y.
(x, y) ∈ S means that
x − y/ 2
is an integer.
T = {(4, 7), (6, 5), (6, 7)}.
a. Draw arrow diagrams for R, S, and T .
b. Indicate whether any of the relations R, S, and T are
functions.

jim_thompson5910 · Answer

Do you know what the notation `(x, y) ∈ A × B` means?

blackstreet23 · Answer

yes

blackstreet23 · Answer

coordinates that belong to the cross section of A and b

blackstreet23 · Answer

or maybe not lol. Could you explain just in case i may have a gap with that

blackstreet23 · Answer

@jim_thompson5910

jim_thompson5910 · Answer

A X B is a set of all ordered pairs (x,y) such that x is in A, y is in B

what I like to do is make a table that is 3x3. 

3 rows because there are 3 elements in B
3 columns because there are 3 elements in A

along the top, I put the elements of set A
along the left side, I put the elements of set B

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blackstreet23 · Answer

I got R correctly. but i dont get the right answer for S

blackstreet23 · Answer

For R i just followed the condition

jim_thompson5910 · Answer

actually it might be better to swap the places of A and B

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